Please help me with this Physics question?

A 12.0 kg Steel block is resting on a horizontal table. The coefficient of static friction is 0.70. Find the minimum force needed to start the block moving.

A) 35.3 N
B) 80.4 N
C) 82.4 N
D) 86.4 N

Thermal energy also known as 'heat energy' is a form of kinetic energy.

When action potentials reach the end of the axon, they stimulate opening of Ca2+ channels, causing a release of neurotransmitters to the post-synaptic cell. How does and impulse propagate down the axon? The stimulus causes a start of the action potential and it moves down the axon without the ions moving down

Mechanical advantage

Answer:

Mechanical Advantage

Explanation:

A) the sound waves were pushed closer together

Answer:

The correct choice is

A) the sound waves were pushed closer together.

Explanation:

As the ambulance gets closer, the distance between the ambulance and marge decreases and so does the wavelength of the siren observed by marge. As the wavelength decrease and speed remains the same for the siren, the frequency of the siren increases because wavelength, frequency and speed are related as

Frequency = Speed/wavelength

Clearly, the frequency is inversely related to wavelength.

Answer:

both energy will remain constant and potential energy must be more than the kinetic energy of the block

So correct Graph will be

A) option

Explanation:

As we know that kinetic energy of the block is given as

[tex]K = \frac{1}{2}mv^2[/tex]

potential energy is given as

[tex]U = mgh[/tex]

so when a block is stationary at the surface of table so due to height of the table the potential energy of the block is given as

[tex]U = mgh[/tex]

but as we know that the speed of the block is zero

so kinetic energy must be

[tex]K = 0[/tex]

so here in the graph both energy will remain constant and potential energy must be more than the kinetic energy of the block

sound waves even if no one is around to hear it.

A falling tree in a forest creates a sound wave. This is caused by the energy of the tree disturbing the atoms in the air, causing them to vibrate and create a wave. Sound can only be produced where there is matter like air or water.

When a tree falls in a forest, it creates a disturbance in the air around it. This disturbance of air particles initiates a sound wave. Sound waves are a type of wave that our ears have evolved to detect.

As the tree makes impact, the energy transfers to the atoms in the air, causing them to vibrate. These vibrations then spread from particle to particle, creating a wave that travels through the air. This is the definition of sound in physics, regardless of whether there is anyone present to hear it or not.

However, it's important to note that these sound waves would only be produced in an environment that has matter (like air or water) for the wave to travel through. In space, where there is a vacuum, no sound would be produced if a tree fell because there would be no matter to disturb.

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Answer:

1. When light passes from a more dense to a less dense substance the light is refracted.

2. The diamond would act like a prism and make rainbows.

3. You observe all of these pretty much every day. Like if you notice how on a glass building it reflects the sunlight and some other things around it. Then another example could be just shining a flash light in a room.

I do FLVS and I got a 100 on this assignment so I hope it helped a little :)

(a) 3539 N/m

Hook's law states that:

[tex]F=kx[/tex]

where F is the force applied on the spring, k is the spring constant, x is the stretching of the spring.

In this problem, we have:

[tex]F=mg=(65.0 kg)(9.8 m/s^2)=637 N[/tex] is the force applied (the weight of the fish)

[tex]x=0.180 m[/tex] is the stretching of the spring

Solving the equation for k, we find the spring constant:

[tex]k=\frac{F}{x}=\frac{637 N}{0.180 m}=3539 N/m[/tex]

(b) 0.85 s

The period of oscillation of a spring-mass system is

[tex]T=2 \pi \sqrt{\frac{m}{k}}[/tex]

In this case,

m = 65.0 kg

k = 3539 N/m

Substituting into the formula,

[tex]T=2 \pi \sqrt{\frac{65.0 kg}{3539 N/m}}=0.85 s[/tex]

(c) 0.37 m/s

The initial elastic potential energy of the spring when the fish is pulled down is:

[tex]U=\frac{1}{2}k\Delta x^2[/tex]

where

[tex]\Delta x = 5.00 cm=0.05 m[/tex] is the stretching of the spring with respect to the initial position

Substituting,

[tex]U=\frac{1}{2}(3539 N/m)(0.05 m)^2=4.4 J[/tex]

The spring reaches its maximum speed when it crosses the equilibrium position, for which [tex]\Delta x=0[/tex], so when all the elastic potential energy has been converted into kinetic energy:

[tex]E=K=\frac{1}{2}mv^2[/tex]

where v is the speed of the fish. Solving for v, we find

[tex]v=\sqrt{\frac{2E}{m}}=\sqrt{\frac{2(4.4 J)}{65.0 kg}}=0.37 m/s[/tex]

The force constant of the spring is  3.53 * 10^3 N/m,  the period of oscillation of the fish is 0.115 s and  the maximum speed it will reach is 0.869 m/s

A proud deep-sea fisherman hangs a 65.0-kg fish from an ideal spring having negligible mass. The fish stretches the spring 0.180 m.

By using the amount of the spring is stretched by the weight of the fish, we can calculate the force  constant [tex]k[/tex] of the spring.

[tex]T = 2\pi \sqrt{\frac{m}{k} }[/tex] with [tex]v_{max}=\omega A = 2 \pi f A[/tex]

When the fish hangs at rest the upward spring force   [tex]|F_x| = kx[/tex] equals the weight [tex]mg[/tex]of the  fish [tex]f = \frac{1}{T}[/tex].  Therefore the amplitude of the SHM is [tex]0.0500 m.[/tex]

a)Find the force constant of the spring. Express your answer with the appropriate units.

[tex]mg=kx\\k = \frac{mg}{x}  \\k = \frac{65*9.8}{0.180} = 3.53 * 10^3 N/m\\[/tex]

b)The fish is now pulled down 5.00 cm and released. What is the period of oscillation of the fish? Express your answer with the appropriate units.

[tex]T = 2\pi \sqrt{\frac{m}{k}[/tex]

[tex]T = 2\pi \sqrt{\frac{65 kg}{ 3.53*10^3 N/m} [/tex]

 [tex]T =0.115 s[/tex]

c)What is the maximum speed it will reach?

[tex]v_{max}=\omega A = 2 \pi f A\\v_{max}=\omega A = \frac{ 2 \pi A}{T} \\v_{max}=\omega A = \frac{ 2 \pi 0.05 m}{0.115}\\v_{max}=\omega A = 0.869 m/s[/tex]

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Answer:

-0.805 m

Explanation:

The x-component of a vector is given by:

[tex]v_x = v cos \theta[/tex]

where

v is the magnitude of the vector

[tex]\theta[/tex] is the angle of the vector with respect to the positive x-direction

In this problem we have

v = 0.888 m

[tex]\theta=205^{\circ}[/tex]

so we have

[tex]v_x = (0.888 m)(cos 205^{\circ})=-0.805 m[/tex]

What is the outcome variable in this experiment?

The dependent variable which is the outcome of bubbles produced.

Keesha did an experiment to study the rate of photosynthesis in the water plant Elodea.

My guess would be that since we initially know what the experiment is for, the key phrase is:

Keesha counted the bubbles released from the plant every minute for five minutes (min). She repeated the process two more times.

The outcome of the bubbles that are produced will be the dependent variable.

In conclusion, the key phrase that's vital in knowing what Keesha is looking for was "Keesha counted the bubbles released from the plant every minute for five minutes".

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Answer:

2f

Explanation:

The relationship between the speed of a sound wave (v), its frequency (f) and its wavelength is

[tex]v=\lambda f[/tex]

For the first wave speed, we have

[tex]v=\lambda f[/tex] (1)

Since the speed of a sound wave depends only on the medium, we can say that the second wave travels at same speed v (because it is still travelling in air, as the first wave). The wavelength of the second wave is [tex]\frac{\lambda}{2}[/tex], so if we call its frequency f', the new equation is

[tex]v=\frac{\lambda}{2}f'[/tex] (2)

And if we equate (1) and (2), we find

[tex]\lambda f = \frac{\lambda}{2}f'\\f'=2f[/tex]

The frequency of the second sound wave is 2f

[tex]\texttt{ }[/tex]

Let's recall the speed of wave formula as follows:

[tex]\large {\boxed {v = \lambda f}}[/tex]

f = frequency of wave ( Hz )

v = speed of wave ( m/s )

λ = wavelength ( m )

Let's tackle the problem!

[tex]\texttt{ }[/tex]

Given:

frequency of first wave = f

wavelength of first wave = λ

wavelegnth of second wave = λ/2

Asked:

frequency of second wave = f' = ?

Solution:

Because the speed of wave depends on the medium, then:

[tex]\texttt{Speed of First Wave = Speed of Second Wave}[/tex]

[tex]v_1 = v_2[/tex]

[tex]\lambda_1 f_1 = \lambda_2 f_2[/tex]

[tex]\lambda f = \frac{1}{2}\lambda f'[/tex]

[tex]f = \frac{1}{2} f'[/tex]

[tex]f' = 2f[/tex]

[tex]\texttt{ }[/tex]

The frequency of the second sound wave is 2f

[tex]\texttt{ }[/tex]

[tex]\texttt{ }[/tex]

Grade: College

Subject: Physics

Chapter: Sound Waves

[tex]\texttt{ }[/tex]

Keywords: Sound, Wave , Wavelength , Doppler , Effect , Policeman , Stationary , Frequency , Speed , Beats, Medium, Space

Answer:

1. Changing the magnetic field intensity

2. Changing the area enclosed by the loop

3. Changing the orientation of the loop of wire with respect to the magnetic field

Explanation:

Electromagnetic induction occurs when there is a variation of magnetic flux through a coil of wire: as a result, an emf (electromotive force) is induced in the coil, according to the equation

[tex]\epsilon=-\frac{\Delta \Phi}{\Delta t}[/tex]

where

[tex]\Delta \Phi[/tex] is the variation of magnetic flux through the coil

[tex]\Delta t[/tex] is the time elapsed

The magnetic flux through a coil of wire is given by:

[tex]\Phi = BA cos \theta[/tex]

where

B is the magnetic field intensity

A is the area enclosed by the coil

[tex]\theta[/tex] is the angle between the direction of B and the perpendicular to the area enclosed by the coil

As we can see, the magnetic flux depends on these three factors, so changing any of them will change the magnetic flux, and an electromotive force will be induced in the coil as a result.

Voltage can be induced in wire loops by changing the magnetic field passing through the loop, physically moving the wire within a stationary magnetic field, or altering its electrical resistance.

There are three primary ways in which voltage can be induced in a loop of wire:

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Kinetic (mechanical) energy

electric fields and magnetic fields both exhibit similar properties. where magnetic fields are natural electric fields are not but man made and can do the same things as a magnetic field.

Answer:

Explanation:

its the name of an element

A chemical symbol represents the name of an element. These symbols are abbreviations used for chemical elements or compounds in chemistry.

A chemical symbol in Chemistry stands for the name of an element. Chemical symbols are abbreviations used in chemistry for chemical elements, functional groups or chemical compounds. These symbols consist of letters - for example, the symbol for Hydrogen is H, Oxygen is O, and Carbon is C.

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When light travels from air into water, it slows down and bends towards the normal, due to the higher refractive index of water compared to air. This change in speed and direction is known as refraction. It's explained by Snell's law of refraction.

When light travels from air into water, it notices a change in speed, due to the difference in the refractive indices of the two mediums. This change in speed causes the light to change direction, a phenomenon we know as refraction. Since the index of refraction for water (approx 1.33) is higher than that of air (approx 1.0003), the light slows down and bends towards the normal upon entering the water from the air. This is based on Snell's law of refraction, expressed as n₁ sin 0₁ = n₂ sin 0₂, where n represents the index of refraction and 0 represents the angle of incidence. Thus, the higher index of refraction in water than in air causes the beam of light to refract towards the normal.

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Well hydrogen would be the main element, as a process called nuclear fusion with both helium and hydrogen atoms occurs within stars. And planets are the products of dead stars that have burned through their supplies of hydrogen, helium, and carbon. Planets are a product of this.

Stars and planets are mainly composed of hydrogen and helium, making up from 96 to 99% of their total mass. They also contain heavier elements, the concentrations of which vary among different stars. This fundamental composition was first discovered by Cecilia Payne-Gaposchkin in 1925.

The stars and planets in the universe are composed mainly of hydrogen and helium, as determined through analyses of stellar spectra. These elements constitute from 96 to 99% of the total mass of most stars. However, they also contain heavier elements in varying quantities. For instance, Population I stars, like the Sun, contain around 1-4% of heavy elements. However, Population II stars found in the outer galactic halo and in globular clusters have much lower concentrations.

These elements must have been fused somewhere. The stars, having incredibly high temperatures, are speculated to be the source of this element formation. Therefore, stars are believed to play a critical role in the chemical richness that characterizes our world.

The discovery that stars are primarily composed of light gases like hydrogen and helium was first made in a pioneering thesis by Cecilia Payne-Gaposchkin in 1925, making a significant contribution to our understanding of the universe. This composition is also found in the material between the stars, with about 99% of it being a gas composed of individual atoms or molecules of hydrogen and helium.

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I see TWO statements here:

#1).   Earth is much farther away from the Sun in Winter.

#2).  That's what makes it cold in the Winter.

Let's use our heads on #1 for just a little moment:

--  When it's Winter in Canada, the USA, and France, it's Summer in Australia, Paraguay, and Namibia.  This is the end of December, all of January and February, and most of March.

-- When it's Winter in Tasmania, South Africa, and Botswana, it's Summer in Germany, Israel, and Mexico.  This is the end of June, all of July and August, and most of September.

So WHOSE Winter is the question asking about ? ?  It doesn't say.

Earth is FARTHEST away from the Sun during the first week in July, and it's NEAREST to the Sun during the first week in January.

The difference between the nearest distance and the farthest distance is about 3%.  It has almost ZERO effect on how hot or cold the days are.  Anywhere !

So BOTH of the statements in the question are FALSE.

electric potential

Electric potential is the electric potential energy per unit charge.

Mathematically; V =PE/q

Where; PE is the electric potential energy, V is the electric potential and q is the charge.

Electric potential is more commonly known as voltage.  If you know the potential at a point, and you then place a charge at that point, the potential energy associated with that charge in that potential is simply the charge multiplied by the potential.

Answer:

c. electric potential

Explanation:

on edg

Answer:

1) F=ma  

a=(mh*g)/(7/5ms+1/2md+mh)

2) same answer as 1 because it is a system

3)a=alpha*R

alpha=a/Rd (use a from 1)

4) similar to 3

alpha=a/Rs

5)F=ma

T=ms*a

T=7/5ms*a (a from 1)  

6)T=mh(g-a)

7)d=1/2at^2 (position formula - starting position and velocity are zero)

t=sqrt(2d/a) (use a from 1)

8)vf^2=vi^2 +2ad (initial velocity = 0)

vf=sqrt(2ad)

9)omega=v/Rs

Explanation:

The question involves a complex system of objects linked by a string and requires an understanding of principles like tension, angular and linear acceleration, and gravity. Using Newton's laws of motion and rotation, as well as a free-body diagram, one can identify linear and angular accelerations and string tension. The time taken for the hoop to fall can be calculated using an equation of motion.

This is a complex system of objects attached to a string and it involves a number of different physical principles such as gravity, tension, angular acceleration, linear acceleration, and moment of inertia.

The linear acceleration of the hoop and the sphere, as well as the angular acceleration of the disk pulley and the sphere, can be identified using the Second Law of Motion (Net Force = mass x acceleration) and Newton's second law for rotation (Net Torque = Moment of Inertia x Angular Acceleration).

The tension in the string can be obtained using free-body diagrams for each object and writing equations for gravitational force and tension.

The time taken by the hoop to fall a certain distance can be calculated using the equation of motion. However, this is a complicated problem and might be better solved using numerical methods or advanced physics concepts.

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Answer:

2940 kg m/s

Explanation:

First of all, we need to find the final velocity of the motorcycle when it hits the ground. The horizontal component of the velocity is zero, so we can just find the vertical component, which is given by:

[tex]v_y = v_0+gt[/tex]

where

v0 =0 is the initial vertical velocity

g = 9.8 m/s^2 is the acceleration due to gravity

t = 3 s is the time of the fall

Substituting into the formula, we find

[tex]v_y=0+(9.8 m/s^2)(3 s)=29.4 m/s[/tex]

And so, we can now find the momentum of the motorcycle upon hitting the ground, which is given by the product between the mass and the velocity:

[tex]p=mv=(100 kg)(29.4 m/s)=2940 kg m/s[/tex]

The motorcycle's momentum when hitting the ground is calculated using the formulas for momentum and velocity. With a mass of 100 kg and a velocity calculated as 29.4 m/s, the motorcycle's momentum is 2940 kg.m/s.

In this case, we are asked to find the momentum of the motorcycle when it hits the ground. The momentum (p) of an object is calculated by the formula p=mv where m is the mass and v is the velocity. The velocity of the motorcycle can be calculated using the formula v=gt, where g is the acceleration due to gravity (9.8 m/s2) and t is the time. So, v=9.8*3 = 29.4 m/s. Therefore, the momentum of the motorcycle is p=100*29.4 = 2940 kg.m/s. Compared to the typical automobile with a momentum of 1400*15 = 21000 kg.m/s, the motorcycle has significantly less momentum due to its smaller mass and velocity.

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a. [tex]11.28\Omega[/tex]

The equivalent resistance of a series combination of two resistors is equal to the sum of the individual resistances:

[tex]R_{eq}=R_1 + R_2[/tex]

In this circuit, we have

[tex]R_1 = 7.25 \Omega\\R_2 = 4.03 \Omega[/tex]

Therefore, the equivalent resistance is

[tex]R_{eq}=7.25 \Omega + 4.03 \Omega=11.28 \Omega[/tex]

b. 5.8 V, 3.2 V

First of all, we need to determine the current flowing through each resistor, which is given by Ohm's law:

[tex]I=\frac{V}{R_{eq}}[/tex]

where V = 9.00 V and [tex]R_{eq}=11.28 \Omega[/tex]. Substituting,

[tex]I=\frac{9.00 V}{11.28 \Omega}=0.8 A[/tex]

Now we can calculate the potential difference across each resistor by using Ohm's law again:

[tex]V_1 = I R_1 = (0.8 A)(7.25 \Omega)=5.8 V[/tex]

[tex]V_2 = I R_2 = (0.8 A)(4.03 \Omega)=3.2 V[/tex]

The equivalent resistance of the circuit is 11.28 Ω, and the current through the circuit is approximately 0.798 A. The potential differences across the 7.25 Ω resistor and the 4.03 Ω resistor are approximately 5.79 V and 3.21 V, respectively.

To solve the problem, we need to brreak it down in the following steps:

Part a):

Part b):

Thus, the potential differences across the resistors are approximately 5.79 V and 3.21 V, respectively.

Choose a heavier bat

Final answer:

To boost momentum, a batter is suggested to choose a heavier bat due to its larger moment of inertia and the greater force it can impart on the ball, according to the principles of moment of inertia, angular momentum, and Newton's third law of motion.

Explanation:

To increase momentum at the plate, a batter can choose a heavier bat. This is because a more massive bat has more inertia and therefore, when swung, will impart a larger force on the ball for the same amount of time compared to a lighter bat. This is evident from the concepts of moment of inertia and angular momentum. When a bat is swung, the moment of inertia plays a role in determining the bat's resistance to changes in its rotational speed. A heavier bat, generally, has a larger moment of inertia, allowing it to maintain its speed through the batting zone and thus create a more forceful impact, enhancing the ball's exit velocity.

Considering the batter swinging a Wiffle ball bat, swinging at the end, furthest from the pivot point, increases the moment of inertia and thus requires more torque to achieve the same angular acceleration as grabbing the middle. However, the increased distance from the pivot allows for a higher linear speed at the end of the bat, creating a larger angular momentum on contact which could result in a more powerful impact if the batter can successfully swing the bat quickly.

In a collision, such as a bat hitting a ball, both objects exert forces on each other, as explained by Newton's third law of motion. This interaction also informs us that not only the ball is affected by the bat but the force exerted by the ball also impacts the bat, as any baseball player who has felt the sting of a ball hit off the end of the bat can attest.

Well , its a easy problem  

By ohms law,  

we have V= IR  

Where V is the voltage applied across the wire and R is the resistance and I is the current  

=> R = V/I  

=> R = 12/0.3 = 40 ohm

The  resistance of the copper wire will be 400 ohms. Resistance is found as the ratio of the voltage and electric current.

Resistance is a type of opposition force due to which the flow of current is reduced in the material or wire. Resistance is the enemy of the flow of current.

The given data in the problem is;

V is the voltage= 12 V

I is the current = 0.30A

R is the resistance

The resistance of the circuit from the Ohm's law is found as;

[tex]\rm V= IR \\\\ R = \frac{V}{I} \\\\\ R = \frac{12}{0.30} \\\\\ R =400 \ ohm[/tex]

Hence, the resistance of the copper wire will be 400 ohms.

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5250/750 m³ or 7 m³

formula is density x volume = mass

Answer:

Volume of wood, [tex]V=7\ m^3[/tex]

Explanation:

It is given that,

Mass of wood, m = 5250 kg

The density of wood, [tex]d=750\ kg/m^3[/tex]

We need to calculate the volume of wood. It can be calculate using the formula of density. It is given by :

[tex]d=\dfrac{m}{V}[/tex]

[tex]V=\dfrac{m}{d}[/tex]

[tex]V=\dfrac{5250\ kg}{750\ kg/m^3}[/tex]

[tex]V=7\ m^3[/tex]

So, the volume of wood is 7 cubic meter. Hence, this is the required solution.

Answer:

3.73 m/s^2

Explanation:

The period of a simple pendulum is given by

[tex]T=2\pi \sqrt{\frac{L}{g}}[/tex] (1)

where

L is the length of the pendulum

g is the gravitational acceleration on the planet

The pendulum in the problem has length

L = 0.640 m

and makes 10 oscillations in 26.0 s; it means that its frequency is

[tex]f=\frac{10}{26 s}=0.385 Hz[/tex]

And so its period is

[tex]T=\frac{1}{f}=\frac{1}{0.385 Hz}=2.6 s[/tex]

So now we can solve equation (1) using L=0.640 m and T=2.6 s, so we can find the value of g on the planet:

[tex]g=(\frac{2\pi}{T})^2L=(\frac{2\pi}{2.6 s})^2 (0.640 m)=3.73 m/s^2[/tex]

Answer:

4. At twice the distance the field strength will be 1/4 of the original value

Explanation:

The magnitude of the electric field produced by an isolated poitn charge is

[tex]E=k\frac{q}{r^2}[/tex]

where

k is the Coulomb's constant

q is the charge

r is the distance from the charge

In this problem, the distance from the charge is doubled from 4 m to 8 m:

[tex]r'=2 r[/tex]

Therefore, the new electric field will be

[tex]E'=k\frac{q}{(r')^2}=k\frac{q}{(2r)^2}=k\frac{q}{4r^2}=\frac{1}{4}E[/tex]

So, the field strength is 1/4 of the original value.

By doubling the distance between two charges the field strength will be    [tex]\dfrac{1}{4} th[/tex]  of the original value.

The formula for the magnitude of the electric field is given by  

[tex]E=k\dfrac{q}{r^2}[/tex]

Here

k is the Coulomb's constant

q is the charge

r is the distance from the charge

It is given in the problem that the distance from the charge is doubled from 4 m to 8 m:

[tex]r'=2r[/tex]

So to find the new electric field

[tex]E'=k\dfrac{q}{r^2} = k\dfrac{q}{(2r)^2} =\dfrac{1}{4} k\dfrac{q}{r^2} =\dfrac{1}{4} E[/tex]

Thus By doubling the distance between two charges the field strength will be    [tex]\dfrac{1}{4} th[/tex]  of the original value.

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Answer:

241 kPa

Explanation:

The ideal gas law states that:

[tex]pV=nRT[/tex]

where

p is the gas pressure

V is its volume

n is the number of moles

R is the gas constant

T is the absolute temperature of the gas

We can rewrite the equation as

[tex]\frac{pV}{T}=nR[/tex]

For a fixed amount of gas, n is constant, so we can write

[tex]\frac{pV}{T}=const.[/tex]

Therefore, for a gas which undergoes a transformation we have

[tex]\frac{p_1 V_1}{T_1}=\frac{p_2 V_2}{T_2}[/tex]

where the labels 1 and 2 refer to the initial and final conditions of the gas.

For the sample of gas in this problem we have

[tex]p_1 = 98 kPa=9.8\cdot 10^4 Pa\\V_1 = 750 mL=0.75 L=7.5\cdot 10^{-4}m^3\\T_1 = 30^{\circ}C+273=303 K\\p_2 =?\\V_2 = 250 mL=0.25 L=2.5\cdot 10^{-4} m^3\\T_2 = -25^{\circ}C+273=248 K[/tex]

So we can solve the formula for [tex]p_2[/tex], the final pressure:

[tex]p_2 = \frac{p_1 V_1 T_2}{T_1 V_2}=\frac{(9.8\cdot 10^4 Pa)(7.5\cdot 10^{-4} m^3)(248 K)}{(303 K)(2.5\cdot 10^{-4} m^3)}=2.41\cdot 10^5 Pa = 241 kPa[/tex]

Answer:

241 kPA

Explanation:

I just did the quest assignment, it was correct

Answer:

D) the second at the doorknob

Explanation:

The torque exerted by a force is given by:

[tex]\tau = Fdsin \theta[/tex]

where

F is the magnitude of the force

d is the distance between the point of application of the force and the centre of rotation

[tex]\theta[/tex] is the angle between the direction of the force and d

In this problem, we have:

- Two forces of equal magnitude F

- Both forces are perpendicular to the door, so [tex]\theta=90^{\circ}, sin \theta=1[/tex]

- The first force is exerted at the midpoint of the door, while the 2nd force is applied at the doorknob. This means that d is the larger for the 2nd force

--> therefore, the 2nd force exerts a greater torque

Gravitational Potential energy is the energy stored with regard to position.

the equation for potential energy is as follows

P.E = mass x gravitational acceleration x height from the ground

gravitational acceleration - 9.8 ms⁻²

substituting the values in the equation

P.E = 125 kg x 9.8 ms⁻² x 1500 m

P.E = 1 837 500 J

therefore the potential energy of the diver at 1500 m high is 1 837 kJ

The potential energy of the skydiver from the given height is 1837.5kJ.

Given the data in the question;

Potential energy; [tex]U = \ ?[/tex]

Gravitational potential energy is simply the potential energy an object possesses in relation to another object due to gravity.

It is expressed as:

[tex]U = mgh[/tex]

Where m is the mass of the object, h is its height from ground level and g is acceleration due to gravity ( [tex]g = 9.8m/s^2)[/tex]

Now, to determine the potential energy of the diver, we substitute our values into the expression above.

[tex]U = mgh\\\\U = 125kg\ *\ 9.8m/s^2\ *\ 1500m\\\\U = 1837500kgm^2/s^2\\\\U = 1837500J\\\\U = 1837.5kJ[/tex]

Therefore, the potential energy of the skydiver from the given height is 1837.5kJ.

Learn more about gravitational potential energy: https://brainly.com/question/19768887