Your neighbor Paul has rented a truck with a loading ramp. The ramp is tilted upward at 35 ∘, and Paul is pulling a large crate up the ramp with a rope that angles 20 ∘ above the ramp. Paul pulls with a force of 350 N. (Force is measured in newtons, abbreviated N.)

Answer:

Right

Explanation:

Because of the Coriolis effect, surface ocean currents are deflected to the Right of their path of motion in the Northern Hemisphere.

Since the Earth is revolving on its axis, flowing air in the Northern Hemisphere are deflected to the right and in the Southern Hemisphere to the left. The consequence of Coriolis is called this deflection.

Answer:

Angular speed ω=3771.4 rad/min

Revolution=5921 rpm

Explanation:

Given data

[tex]d=28in\\r=d/2=28/2=14in\\v=50mi/hr[/tex]

To find

Angular speed ω

Revolution per minute N

Solution

First we need to convert the speed of truck to inches per mile

as

1 mile=63360 inches

1 hour=60 minutes

so

[tex]v=(50*\frac{63360}{60} )\\v=52800in/min[/tex]

Now to solve for angular speed ω by substituting the speed v and radius r in below equation

[tex]w=\frac{v}{r}\\ w=\frac{52800in/min}{14in}\\ w=3771.4rad/min[/tex]

To solve for N(revolutions per minute) by substituting the angular speed ω in the following equation

[tex]N=\frac{w}{2\pi }\\ N=\frac{3771.4rad/min}{2\pi }\\ N=5921RPM[/tex]  

To find the angular speed of the wheels, convert the speed from miles per hour to inches per minute, and calculate using the formula Angular Speed = Linear Speed / Radius. The wheels make Revolutions per Minute which can be found by dividing the angular speed in radians per minute by 2π.

To find the angular speed of the wheels in rad/min, we need to use the formula:
Angular Speed = Linear Speed / Radius

First, let's convert the speed from miles per hour to inches per minute. There are 5,280 feet in a mile and 12 inches in a foot. So, 50 miles/hour is equal to:
(50 miles/hour) x (5,280 feet/mile) x (12 inches/foot) x (1 hour/60 minutes)

Next, we need to convert the diameter of the wheel to the radius. Since the diameter is given in inches, the radius is half the diameter:
Radius = 28 in./2 = 14 in.

Using these values, we can calculate the angular speed:

Angular Speed = (Linear Speed / Radius)

To find the number of revolutions per minute (rpm) the wheels make, we need to divide the angular speed in radians per minute by 2π (the number of radians in a full revolution):
Revolutions per Minute = Angular Speed (in rad/min) / 2π

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Answer:

The possible range of wavelengths in air produced by the instrument is 7.62 m and 0.914 m respectively.

Explanation:

Given that,

The notes produced by a tuba range in frequency from approximately 45 Hz to 375 Hz.

The speed of sound in air is 343 m/s.

To find,

The wavelength range for the corresponding frequency.

Solution,

The speed of sound is given by the following relation as :

[tex]v=f_1\lambda_1[/tex]

Wavelength for f = 45 Hz is,

[tex]\lambda_1=\dfrac{v}{f_1}[/tex]

[tex]\lambda_1=\dfrac{343}{45}=7.62\ m[/tex]

Wavelength for f = 375 Hz is,

[tex]\lambda_2=\dfrac{v}{f_2}[/tex]

[tex]\lambda_2=\dfrac{343}{375}=0.914\ m/s[/tex]

So, the possible range of wavelengths in air produced by the instrument is 7.62 m and 0.914 m respectively.

Explanation:

Electric field is the ratio of force and charge.

Electric field, E = 280000 N/C

Charge, q = -7.9 C

We have

                 [tex]E=\frac{F}{q}\\\\280000=\frac{F}{7.9}\\\\F=280000\times 7.9\\\\F=2.21\times 10^6N[/tex]

The magnitude of the force that acts on a charge of -7.9C at this spot is 2.21 x 10⁶ N.

Final answer:

The magnitude of the force that acts on a -7.9 C charge in a 280000 N/C electric field is 2212000 N, acting in the opposite direction of the electric field.

Explanation:

The question asks about the magnitude of the force that acts on a charge in the presence of an electric field. This can be solved by using the equation F = qE, where F is the force in Newtons, q is the charge in Coulombs, and E is the electric field strength in Newtons per Coulomb (N/C).

Given that the electric field (E) is 280000 N/C and points due west, and the charge (q) is -7.9 C, we can calculate the force as follows:

F = qE = (-7.9 C) × (280000 N/C) = -2212000 N.

This result indicates the magnitude of the force is 2212000 N, and by convention, the negative sign indicates that the force direction is opposite to the direction of the electric field; since the electric field points west, the force on the negative charge points east.

Answer:A) Risk(R)= $1000

B) There is justification for spending an additional cost of $100 to prevent a corrosion whose consequence in monetary terms is $1000

Explanation:R= Risk,

P=Probability of failure

C= Consequence of failure

Mathematically, R=P ×C

10 out of 1000 carbon-steal products failed

Probability of failure= 10/1000 =0.01

The consequence of failure by corrosion given in monetary term =$100,000

Risk of failure = 0.01 × $100,000

R=$1000

Answer:

speed of molecule ∝  1/mass of molecule.

Explanation:

The velocities of the molecules depend on their masses. That's because if the molecules are large in size, their velocity is slower. Therefore their velocity is quicker when their size is small, since the molecules can move faster.

Therefore , it can be written as

speed of molecule ∝  1/mass of molecule.

Answer:

time of fall and the final velocity

Explanation:

the mass of solid ball is more than the mass of hollow ball.

According to the third equation of motion

v² = u² + 2gh

As the final velocity v does not depend on the mass of the object, so the final velocity of both the ball is same.

According to the first equation of motion

v = u + gt

As v is same for both the balls, the time is also same for both the balls.

So, they both have same time of fall and final velocity.

The work done by a gas when it expands against a constant external pressure can be calculated using the formula W = -P∆V. For a helium gas expanding from 5.30 L to 23.70 L against an external pressure of 0.981 atm, the work done is -1.8299164 kJ. The change in internal energy is the heat added plus the work done on the system, resulting in a change of 28.93 kJ.

To calculate the work done by the helium gas during its expansion against a fixed external pressure, we can use the formula for work, which is:

W = -P∆V

where:

- W is the work done on or by the gas (in joules, J)

- P is the external pressure (in pascals, Pa)

- ∆V is the change in volume (in cubic meters, m3)

Firstly, we need to convert the pressure from atm to Pa and volume from L to m3:

1 atm = 101325 Pa
1 L = 0.001 m3

Thus:

P = 0.981 atm × 101325 Pa/atm = 99456.325 Pa
∆V = (23.70 L - 5.30 L) × 0.001 m3/L = 0.0184 m3

Work done, W = -P∆V = -99456.325 Pa × 0.0184 m3 = -1829.9164 J

The work done by the gas is negative, indicating that it was done on the surroundings. Converting Joules to kilojoules (1 J = 0.001 kJ), we have:

W = -1.8299164 kJ

To determine the change in internal energy, we use the first law of thermodynamics, which states:

∆U = Q - W

where:

- ∆U is the change in internal energy
- Q is the heat added to the system

Since we added 27.10 kJ of heat (Q), and work done (W) on the surroundings is -1.8299164 kJ, we can calculate the change in internal energy (∆U) as:

∆U = 27.10 kJ - (-1.8299164 kJ) = 28.9299164 kJ

The change in the helium's internal energy is 28.93 kJ.

Answer:

(B) 0.70 m

Explanation:

Currently taking the test

A cyclist rides at a constant speed of 4.5 m/s around a curve. If the centripetal acceleration is 29 m/s2, the radius of the curve is found as 0.70m.

To find the radius of the curve, the given values are,

Speed = 4.5 m/s,

centripetal acceleration = 29m/s².

Centripetal acceleration is nothing but it always means towards the centre. Any object undergoing or processing in a circular motion which is uniform (uniform circular motion) has a centripetal acceleration and that acceleration is directed radially inwards.

The acceleration which has a magnitude that is equal to the square of the speed of the object along the curve, divided by the distance from the center of the circle to the object in motion.

Mathematically it can be expressed as;

a = [tex]\frac{v^{2} }{r}[/tex]

where

v is the speed (tangential speed)

r is the radius of the curve

In this case, we know the speed, v=4.5 m/s, and the centripetal acceleration, a=29 m/s^2, so we  can re-arrange the equation above to find the radius of the curve:

r =[tex]\frac{v^{2} }{a}[/tex]

= [tex]\frac{4.5^{2} }{29}[/tex]

r= 0.70 m.

The radius of the curve r = 0.70m.

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The refrigerator has consumed more energy

Explanation:

The relationship between power and energy consumed by a device is given by

[tex]E=Pt[/tex]

where

E is the energy

P is the power

t is the time elapsed

For the refrigerator, we have

P = 90 W

[tex]t = 24 h \cdot 3600 = 86400 s[/tex]

Therefore the energy consumed is

[tex]E=(90)(86400)=7.78\cdot 10^6 J[/tex]

For the hair dryer, we have

P = 900 W

[tex]t = 20 min \cdot 60 = 1200 s[/tex]

Therefore the energy consumed is

[tex]E=(900)(1200)=1.08\cdot 10^6 J[/tex]

Therefore, the refrigerator has consumed more energy.

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Answer:

It's helps Emily became when she swims her hair is not in the way creating friction and making her swim faster. friction acts between two metals blocks that slide past each other.

Explanation:

Answer:

I had this same question on a Science test and I chose D) and got it right.

Explanation:

Answer: The speed is 0.4694 m/s.

Explanation:

S.I or M.K.S system has seven fundamental units which are used to find derived units

1) Mass - Kilogram

2) Length - meter

3) Time - Seconds

4) Electric Current - Ampere

5) Amount of substance - Moles

6) Intensity of light - Candela

7) Temperature - Kelvin

The conversion used from miles to feet is:

1 mile = 1609 m

1.000 miles= [tex]\frac{1690}{1}\times 1.000=1690m[/tex]

The conversion used from hour to sec is:

1 hr = 3600 sec

We are asked: 1.000 miles/hr = ? m/s

[tex]1.000miles/hr=\frac{1690}{3600}m/sec=0.4694m/sec[/tex]

Therefore, the speed in SI unit is 0.4694

Answer:

We have to do 864 J for moving the crate

Explanation:

We have given a 880 N crate is at rest on the floor

Frictional force f = 180 N

We have to move the crate by 4.8 m

For moving the crate we have to overcome the frictional force acting the crate

We know that work done is given by [tex]Work\ done=force\times distance[/tex]

Here force will be equal to frictional force and distance is 4.8 m

So work done [tex]W=180\times 4.8=864J[/tex]

So we have to do 864 J for moving the crate

problem is worked out down below in an attachment

Final answer:

It takes approximately 0.015 seconds for a nerve impulse from a stubbed toe to reach the brain, calculated based on the speed of the nerve impulse (100 m/s) and the estimated distance (1.5 meters).

Explanation:

To calculate the time it takes for a nerve impulse to travel from a stubbed toe to the brain, we need to consider the speed of the nerve impulse and the distance it must travel. The speed of a nerve impulse is about 100 m/s. Assuming an average distance from the toe to the brain via the spinal cord is approximately 1.5 meters (taking into account the height of an individual and that nerve paths are not completely straight), we can use the formula:

Time = Distance / Speed

Plugging in the values gives us:

Time = 1.5 m / 100 m/s = 0.015 seconds.

So, it takes approximately 0.015 seconds for a nerve impulse from a stubbed toe to reach the brain. This rapid transmission allows the body to respond quickly to stimuli, protecting it from further injury.

Answer: the answer is true

Explanation:

electronic control units use semiconductors and also they widely use MOSFETS which are transistors as well.

It is true that automotive applications use semiconductors such as diodes, transistors, and power transistors. Semiconductors are the foundation of modern electronic devices and systems, including those in the automotive industry.

The statement is true. Automotive applications such as electronic control units indeed utilize semiconductors like diodes, transistors, and power transistors. Semiconductors are essential for modern electronics, as they can be combined into integrated circuits (ICs) on a single silicon chip, connecting millions of devices with conducting paths. Diodes, for example, only allow current to flow in one direction and are crafted from a p-n junction between a p-type and an n-type semiconductor.

Transistors are also semiconductor devices that have revolutionized modern technology, allowing for the miniaturization of electronic devices. They consist of three layers — the collector, base, and emitter — and can control large currents with small input signals. These components are integral to various electronic systems within vehicles for controlling functions and processing signals.

Answer:

A) d. (1/4)(2000m/s) = 500 m/s

B) c. 4000 J

C) f. None of the above (2149.24 m/s)

Explanation:

A)

The translational kinetic energy of a gas molecule is given as:

K.E = (3/2)KT

where,

K = Boltzman's Constant = 1.38 x 1^-23 J/K

T = Absolute Temperature

but,

K.E = (1/2) mv²

where,

v = root mean square velocity

m = mass of one mole of a gas

Comparing both equations:

(3/2)KT = (1/2) mv²

v = √(3KT)/m  _____ eqn (1)

FOR HYDROGEN:

v = √(3KT)/m = 2000 m/s  _____ eqn (2)

FOR OXYGEN:

velocity of oxygen = √(3KT)/(mass of oxygen)  

Here,

mass of 1 mole of oxygen = 16 m

velocity of oxygen = √(3KT)/(16 m)

velocity of oxygen = (1/4) √(3KT)/m

using eqn (2)

velocity of oxygen = (1/4)(2000 m/s) = 500 m/s

B)

K.E = (3/2)KT

Since, the temperature is constant for both gases and K is also a constant. Therefore, the K.E of both the gases will remain same.

K.E of Oxygen = K.E of Hydrogen

K.E of Oxygen = 4000 J

C)

using eqn (2)

At, T = 50°C = 323 k

v = √(3KT)/m = 2000 m/s

m = 3(1.38^-23 J/k)(323 k)/(2000 m/s)²

m = 3.343 x 10^-27 kg

So, now for this value of m and T = 100°C = 373 k

v = √(3)(1.38^-23 J/k)(373 k)/(3.343 x 10^-27 kg)

v = 2149.24 m/s

The rms speed will be "500 m/s". A further solution is provided below.

Given:

Speed of a diatomic hydrogen molecule,

Mol of diatomic hydrogen,

Temperature,

Now,

The rms speed of diatomic molecule will be:

→ [tex]V_{rms} = \sqrt{\frac{5kT}{m} }[/tex]

or,

→ [tex](V_{rms})O_2 = \sqrt{\frac{5kT}{16(m)} }[/tex]

                  [tex]= \frac{1}{4} (V_{rms})H_2[/tex]

                  [tex]= \frac{1}{2} (2000)[/tex]

                  [tex]= 500 \ m/s[/tex]

Thus the above response is right.  

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Answer:Frequency = 3.525 Hertz

Explanation:In static equilibrium, kd =mg

Where k= effective spring constant of the spring.

mg= The weight of the car.

d= static deflection.

Therefore, w =SQRTg/d

w = SQRT 9.81/0.02

w= 22.15 rad/sec

Converting to Hertz unit for frequency

1 rad/s = 0.1591

22.15rad/s=?

22.15 × 0.1591= 3.525 hertz

The natural frequency of the automobile in the vertical direction is 3.52 Hertz

Static equilibrium refers to the physical state in which the components of a system are at rest and the net force acting through the system is equal to zero.

In static equilibrium:

kd = mg

where;

k = effective spring constant of the spring.

mg = the weight of the car

d = static deflection.

also K = mω²

where ω is angular velocity

m is mass

Thus, mω²d = mg

ω²d = g

ω = √g/d

ω = g/d

ω  = √9.8/0.02

ω = 22.15 rad/sec

1 rad/s = 0.1591 Hertz

22.14 rad/s = 22.14 * 0.1591

22.14 rad/s = 3.525 hertz

Therefore, the natural frequency of the automobile in the vertical direction is 3.52 Hertz

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Answer:

true

Explanation:

Here we have assumed that increasing the mass of a glove will increase the surface area.

Injury is caused by the application of pressure at a point on the body. The application of pressure takes place via the area of the gloves. Pressure is given by

[tex]P=\dfrac{F}{A}[/tex]

where

F = Force

A = Area to which the force is applied

So, a bigger glove will increase the surface area and reduce the pressure resulting in a lower chance of injury.

Hence, the statement is true.

Answer:d

Explanation:

Spring is compressed to a distance of x from its equilibrium position

Work done by block on the spring is equal to change in elastic potential energy

i.e. Work done by block [tex]W=\frac{1}{2}kx^2[/tex]

therefore spring will also done an equal opposite amount of work on the block in the absence of external force

Thus work done by spring on the block [tex]W=-\frac{1}{2}kx^2[/tex]

Thus option d is correct

The work done on a block by a spring it compresses is given by the formula for elastic potential energy, ½ kx^2, with a negative sign because the work is done against the movement of the block. Therefore, the correct answer is B.W=-kx^2.

In this case, the work done on the block by the spring is given by the formula for elastic potential energy, which is ½ kx2. However, this work is done on the block, meaning it loses this amount of energy, so the sign is negative. Therefore, the correct answer is B.W=-kx^2.

This negative sign indicates that the work is done against the movement. As the block is pushed onto the spring, the spring does negative work on the block by pushing back. Think of it as the block 'losing' energy to the spring while it compresses it, which is why the work done by the spring on the block is negative.

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The magnitude of the impulse delivered to the roof is -0.01134 kg·m/s, and the magnitude of the force of the impact is -30.70 N.

The magnitude of impulse delivered to your roof can be calculated using the equation impulse = mass x change in velocity. In this case, the mass of the raindrop is given as 0.0014 g, which is equivalent to 0.0014 kg. The change in velocity is the final velocity (0 m/s) minus the initial velocity (8.1 m/s). Therefore, the magnitude of the impulse is 0.0014 kg x (-8.1 m/s) = -0.01134 kg·m/s.

To calculate the magnitude of the force of the impact, we can use the equation force = impulse/time. In this case, the impulse is the magnitude of the impulse calculated previously (-0.01134 kg·m/s) and the time is given as 0.37 ms, which is equivalent to 0.00037 s. Therefore, the magnitude of the force of the impact is -0.01134 kg·m/s / 0.00037 s = -30.70 N.

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In this physics problem, we calculate both the magnitude of the impulse delivered and the force of impact of a raindrop hitting a roof.

The magnitude of the impulse delivered to the roof can be calculated by multiplying the mass of the raindrop by its velocity.

The magnitude of the force of the impact can be determined using the formula for impulse, considering the time it takes for the raindrop to come to rest.

Answer:

The photon has a wavelength of [tex]1.5x10^{-6}m[/tex]

Explanation:

The speed of a wave can be defined as:

[tex]v = \nu \cdot \lambda[/tex] (1)

Where v is the speed, [tex]\nu[/tex] is the frequency and [tex]\lambda[/tex] is the wavelength.

Equation 1 can be expressed in the following way for the case of an electromagnetic wave:

[tex]c = \nu \cdot \lambda[/tex] (2)              

Where c is the speed of light.    

Therefore, [tex]\lamba[/tex][tex]\lambda[/tex] can be isolated from equation 2 to get the wavelength of the photon.

[tex]\lambda = \frac{c}{\nu}[/tex] (3)

[tex]\lambda = \frac{3.00x10^{8}m/s}{2.00x10^{14}s^{-1}}[/tex]

[tex]\lambda = 1.5x10^{-6}m[/tex]

Hence, the photon has a wavelength of [tex]1.5x10^{-6}m[/tex]        

Summary:  

Photons are the particles that constitutes light.

Answer:

Hi

Final temperature = 250.11 °C

Final volume = 0,1 m3.

Process work = 0

Explanation:

The specific volume in the initial state is: v = 0.1m3/2 kg = 0.05 m3/kg.

This volume is located between the volumes as saturated liquid and saturated steam at 20 °C. For this reason the water is initially in a liquid vapor mixture. As the piston was blocked the volume remains constant and the process is isometric, also known as isocoric process, so the final temperature will be the water temperature at a saturated steam of v=0.05m3/kg, which is obtained by using steam tables for water, by linear interpolation. As follows, using table A-4 of the Cengel book 7th Edition:

v=0.05 m3/kg

v1=0.057061 m3/kg

T1=242.56°C

v2=0.049779 m3/kg

T2=250.35°C

T=[tex]\frac{T2-T1}{v2-v1} x(v-v1)+T1=\frac{250.35°C-242.56°C}{0.049779m3/kg-0.057061m3/kg}x(0.05m3/kg-0.057061m3/kg)+242.56°C=250.11°C[/tex]

The process work is zero because there is no change in volume during heating:

W=PxΔv=Px0=0

where

W=process work

P=pressure

Δv=change of volume, is zero because the piston was blocked so the volume remains constant.

Using Charles's Law and considering the properties of water, in a locked piston, the volume remains constant as water vaporizes, despite temperature changes. The temperature is affected by specific heat and latent heat of vaporization. No work is done as the locked piston prevents expansion.

In this scenario, we would need to use principles from physics to solve this problem, particularly the laws of thermodynamics and the properties of gases and liquids, specifically water. Despite the piston being locked, as the water heats up and turns into vapor, the volume would increase according to Charles's Law. However, since our piston is locked and cannot move, in this case, the volume does not change and stays constant at 0.1 m³.

Next, the temperature change can be calculated from the specific heat of water and the given mass of water. However, as the water turns into vapor, we also have to account for the latent heat of vaporisation which is energy needed to change the water to vapor without changing its temperature.

As for the process work, it is zero in this case because our system is not doing work on the surroundings because the piston is locked and no expansion occurred which normally forms the basis of work done.

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Answer:

time=6.25×10⁻³ seconds

or

time=6.25 Milliseconds

Explanation:

Given Data

Ball mass= 0.50 kg

Force = 240 N

Speed =3.0 m/s

To find

Time

Solution

From Newtons second Law of motion

Force=mass×acceleration

As mass and Force is given we need to Find acceleration

So

Acceleration=Force/mass

Acceleration=240/0.50

Acceleration=480 m/s²

When ball was at rest its velocity at that time was 0.Now the final velocity is given as:

Velocity=acceleration×time

As we have find the acceleration and velocity is given so we can find time easily

So

time=velocity/acceleration

time=(3.0m/s)/480 N

time=6.25×10⁻³ seconds

or

time=6.25 Milliseconds

Using the impulse-momentum theorem, the time the mallet was in contact with the ball can be found to be 0.00625 seconds.

This problem can be solved using the imulse-momentum theorem, which states that the impulse on an object is equal to the change in its momentum. Momentum is calculated as mass times velocity, and impulse is calculated as force times time. In this particular case, we can set the final momentum of the croquet ball, 0.50 kg * 3.0 m/s, equal to the impulse, 240 N * t, the duration of time the mallet was in contact with the ball.

Setting these equal to each other, we get:
240 N * t = 0.50 kg * 3.0 m/s
Solving for t, we get:
t = (0.50 kg * 3.0 m/s) / 240 N
After doing the calculations, we find the duration t to be 0.00625 seconds.

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Answer:

Explanation:

temperature (T) = 25 degrees

volume of water (v) = 2 L = 2000 mL

density of water = 0.997 g/mL

density of ice = 0.917 g/mL

we can get the mass of the water and the use it to get the volume when it freezes to ice, this is because the mass remains the same irrespective of the change of state.

Q: A rock is thrown off of a 100 foot cliff with an upward velocity of 45 m/s. As a result its height after t seconds is given by the formula:

h(t)=100+45t−4.9t2

(a) What is its height after 3 seconds?

(b)What is its velocity after 3 seconds?

Answer:

(a) 190.9 m.

(b) 15.6 m/s upward

Explanation:

Given:

h(t) = 100 + 45t - 4.9t²

The height after 3 seconds,

t = 3 s

Substitute the value of t in to the equation above.

h(3) = 100+45(3)-4.9(3)²

h(3) = 100+135-44.1

h(3) = 190.9 m

Therefore the height after 3 seconds = 190.9 m.

(b) Velocity after 3 seconds

The velocity is obtained by differentiating h(t) with respect to time

v = dh(t)/dt

dh(t)/dt = 45-9.8t

v = 45 - 9.8t ......................................... Equation 1

t = 3 s.

Substitute the value of t into the equation above,

v = 45 - 9.8(3)

v = 45- 29.4

v = 15.6 m/s

Thus the velocity after 3 seconds = 15.6 m/s upward

Final answer:

After 3 seconds, the rock is 190.9 meters high and moving upwards with a velocity of 15.6 m/s. The computations are based on the given formula for height over time.

Explanation:

The question involves determining the height and velocity of a rock thrown off a 100-foot cliff with an upward velocity of 45 m/s after a certain time interval. Given the formula h(t) = 100 + 45t - 4.9t2, where h represents the height in meters and t represents the time in seconds, we can calculate the specific outcomes for the rock at different points in time.

(a) Height after 3 seconds

To find the height after 3 seconds, we substitute t = 3 into the equation: h(3) = 100 + 45(3) - 4.9(3)2 = 100 + 135 - 44.1 = 190.9 meters above the ground.

(b) Velocity after 3 seconds

The velocity of the rock can be found by taking the derivative of the height function, which gives v(t) = 45 - 9.8t. Substituting t = 3: v(3) = 45 - 9.8(3) = 45 - 29.4 = 15.6 m/s, directed upwards.

Explanation:

We have equation of motion v² = u² + 2as

Initial velocity, u = 300 m/s  

Acceleration, a = ?

Final velocity, v = 400 m/s  

Displacement,s = 4 km = 4000 m

Substituting  

v² = u² + 2as

400² = 300² + 2 x a x 4000

a = 8.75 m/s² = 8.8 m/s²

The acceleration is 8.8 m/s²

The answer got is reasonable.

Final answer:

The jet's acceleration, assuming it to be a constant acceleration, is 8.75 m/s². The initial calculation of 8.8 m/s² was close, but using the kinematic equation we find the precise acceleration value.

Explanation:

Let's calculate the jet's acceleration with the given information. We know the initial speed (u), the final speed (v), and the distance (s) covered during acceleration:

We can use the kinematic equation:

v² = u² + 2as

Where:

Plugging in the values:

4002 = 3002 + 2a(4000)

Solving for a gives:

a = (400² - 300²) / (2 × 4000)

a = (160000 - 90000) / 8000

a = 70000 / 8000

a = 8.75 m/s²

Your computation of 8.8 m/s² is quite close but let's ensure we're using the correct figures. The actual acceleration is 8.75 m/s² when calculated correctly, so a slight revision may be needed on your calculation depending on your rounding during the process.

Answer:

400X

Explanation:

Total magnification = power of eyepiece (ocular) ×  power of the objective lenses

= 10X × 40X = 400X

Answer:

PCBs have high electrical resistance and are excellent insulating materials.

Explanation:

Polychlorinated biphenyls [PCBs] are industrial chemical compounds made by man, which contains carbon, hydrogen and chlorine atoms. They can be used in the production of paints and dyes, heat transfer, etc.

There has been the ban on the use of these compounds because they are said to be very stable, and yield slowly to degradation by nature. They have low and not high electrical resistance.  

Answer: They both posses magnitude, have the same unit and are covered in a specific time interval

Explanation:

One of the relationship between average speed and the magnitude of the average velocity for any motion is that the motion are covered in a specific time interval. They both specifies magnitude and are measured using the same unit which is meter per second.

One of their major difference is that average speed only deals with distance covered in a specific time interval (it doesn't specify direction) while velocity is distance covered in a "specified direction" within a time frame.

The relationship between average speed and the magnitude of average velocity is that the average speed can be greater than the magnitude of average velocity. This is particularly the case when the direction of motion changes. Both are the same when the motion is in a constant direction.

The correct statement about the relationship between average speed and the magnitude of average velocity is: Average speed can be greater than the magnitude of average velocity. To understand this, let's consider an example: if you complete a round trip starting and ending at the same location, the total displacement (change in position) will be zero, leading to an average velocity of zero. However, the average speed won't be zero, as the total distance covered isn't zero.

Another important point is that average speed and the magnitude of average velocity are the same only when the direction of motion is constant. Changing direction increases the path covered (distance), which impacts the average speed, but not the displacement, thus not affecting the average velocity.

So, while both 'speed' and 'velocity' measure how fast an object moves, 'velocity' is a vector that includes a direction, and 'speed' is a scalar without direction. Because of the direction component of velocity, the magnitude of average velocity can be less than the average speed.

Learn more about Average speed here:

https://brainly.com/question/1375440

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Answer:

Alpha radiation is a helium nucleus

Electrons are beta radiation

The order of radioactive particles from most to least penetrating ability is gamma, beta, alpha

Alpha radiations is easily stopped by paper or clothing

Explanation:

Answers:

Alpha radiation is a helium nucleus.

Electrons are beta radiation

Alpha radiation is easily stopped by paper or clothing.

The order of radioactive particles from most to least penetrating ability is gamma, beta, alpha.

Beta radiation can be stopped by thick wood or a sheet of aluminum.

Explanation:

1. only unstable nuclei give off radiation. In an unstable atom, the nucleus changes by giving off a neutron to get back to a balanced state. As the unstable nucleus changes, it gives off radiation and is said to be radioactive.

2. Gamma Rays can easily penetrate barriers that can stop alpha and beta particles, such as skin and clothing. several inches of a dense material like lead, or even a few feet of concrete may be required to stop them.

3. Alpha radiation is a helium nucleus.

4. A beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron

5. Gamma rays are a high-energy form of electromagnetic radiation.

6. Alpha radiation is easily stopped by paper or clothing.

7. Alpha denotes the largest particle, and it penetrates the least. Alpha particles carry a positive charge, beta particles carry a negative charge, and gamma rays are neutral.

8. Gamma radiation is a rigid electromagnetic radiation at the short-wave edge of the electromagnetic wave spectrum.

9. Beta particles can travel a few metres through the air and can be stopped by a thin sheet of aluminum or a piece of wood a few centimetres thick.

Hope this Helps!

~A.W.E.S.W.A.N ♥