Answer:
C. 98 N
Explanation:
The force needed to get the skier at rest moving must be at least equal to the maximum static frictional force acting on the skier, which is given by
[tex]F=\mu W[/tex]
where
[tex]\mu = 0.14[/tex] is the coefficient of static friction
W = 700 N is the weight of the skier
Substituting into the equation, we find
[tex]F=(0.14)(700 N)=98 N[/tex]
Answer:
c
Explanation:
μ = f/N where μ is the coefficient of friction; f is the amount of force that resists motion, and N is the normal force. You must solve for f here so 700 N x .14 = 98 N.
The atmosphere is made up of several layers of air. The bottom two layers are the troposphere and the stratosphere. How does the troposphere differ from the stratosphere?
Troposhere is differ from stratosphere by the following reason
1. all weather pheonamena take place in trosphere
2. in trosposphere temperature increase by increasing height which is just opposite in the case of stratosphere
3. the maximum air is found in trosposphere
Final answer:
The troposphere is the earthly atmospheric layer where weather and major atmospheric changes take place due to its high density and temperature that decreases with altitude. Above it sits the stratosphere, which contains the ozone layer, and exhibits a temperature inversion, stability, and a lack of weather phenomena.
Explanation:
Comparison of Troposphere and Stratosphere
The troposphere and stratosphere are the two lowest layers of the Earth's atmosphere. The troposphere is the bottommost layer, where nearly all weather occurs and which houses most of the atmospheric mass. This layer extends from sea level up to about 9 km at the poles and averages 12 km in thickness, reaching up to 17 km at the equator due to the Earth's rotation. The troposphere is characterized by a temperature that decreases with altitude, making it denser near the surface. By contrast, the stratosphere is the second layer that lies above the troposphere, stretching from approximately 12 km to 50 km above Earth's surface. It contains the ozone layer and is known for its temperature inversion, where temperature increases with altitude due to the absorption of ultraviolet radiation by ozone.
The most discernible difference between the troposphere and the stratosphere is the temperature gradient. In the troposphere, temperature generally decreases with altitude, while in the stratosphere, it increases with altitude due to the presence of the ozone layer which absorbs and scatters the Sun's ultraviolet light. This temperature inversion creates a stable layer that prevents convective currents, marking a clear boundary between these two atmospheric layers known as the tropopause.
The troposphere is significantly more turbulent and dynamic, housing all the weather systems and majority of the atmospheric water vapors. Meanwhile, the stratosphere maintains a more stable environment. The difference in density and temperature between the two layers is responsible for the distinctive weather phenomena and atmospheric conditions unique to each layer.
The small currents in axons corresponding to nerve impulses produce measurable magnetic fields. a typical axon carries a peak current of 0.040 μa. what is the strength of the field at a distance of 1.2 mm
Answer:
[tex]6.66\cdot 10^{-12}T[/tex]
Explanation:
The magnetic field produced by a current-carrying wire is given by
[tex]B=\frac{\mu_0 I}{2\pi r}[/tex]
where
[tex]\mu_0[/tex] is the vacuum permeability
I is the current
r is the distance from the wire
In this problem we have
[tex]I=0.040 \mu A=4\cdot 10^{-8}A[/tex]
r = 1.2 mm = 0.0012 m
So the magnetic field strength is
[tex]B=\frac{(4\pi \cdot 10^{-7} H/m)(4\cdot 10^{-8}A)}{2\pi (0.0012 m)}=6.66\cdot 10^{-12}T[/tex]
What happens to steam during condensation
Explanation:
Condensation is the process of changing the physical state of matter, from gas to liquid state. During condensation of matter, the physical state of the matter changes. Now in this question it is asked that what happens to the steam during the process of condensation. So steam is the matter, and during this process, steam converts its molecules from gaseous to the liquid state without heating. After this process, the steam is converted back to its liquid state. The liquid now take less space than that of the gas and exert less pressure on the walls of the container.
Which of the following technologies would produce the most energy in light waves?
A.Halogen lightbulb
B.Radio-controlled toy airplane
C.Microwave industrial drying equipment
D.Ultraviolet disinfecting wand
Answer:
D. Ultraviolet disinfecting wand.
Explanation:
Energy in light waves depends upon the frequency o the waves. Higher the frequency of the waves, higher the amount of energy it carries. Similarly, waves with shorter wavelength has higher frequencies and thus more energy.
Ultraviolet disinfecting wand would produce most energy out of the four options because it produce UV waves which have shorter wavelength and higher frequency.
Answer: (B): Radio-controlled airplane
Explanation:
A P E X
(Please Help, Will Give BRAINLIEST Answer)
A 50.0-kilogram skydiver jumps from an airplane and is in freefall for 20 seconds.
Immediately before she opens her parachute, her kinetic energy is 78,400 joules.
If the amount of heat her motion transferred to her surroundings during freefall was 884,000 joules, how far did she fall during her freefall?
(Assume the skydiver's gravitational potential energy is only transformed into heat and kinetic energy, and assume the rate of acceleration due to Earth's gravity is 9.81 m/s/s.)
A. 1,960 meters
B. 1,560 meters
C. 9,620 meters
Answer:
A
Explanation:
Initial gravitational energy = final kinetic energy + heat
mgh = KE + Q
(50 kg) (9.81 m/s²) h = 78400 J + 884000 J
h = 1960 meters
The weight of an object is the product of its mass, m, and the acceleration of gravity, g (where g=9.8 m/s2). Of an object’s mass is m=10. kg, what is its weight?
Answer:
98 N
Explanation:
The weight of an object is given by
W = mg
where
m is the mass of the object
g = 9.8 m/s^2 is the acceleration of gravity
Here we have an object with mass
m = 10 kg
Therefore, its weight will be
[tex]W=(10 kg)(9.8 m/s^2)=98 N[/tex]
What is the law of conservation of matter
Answer:
The law of conservation of matter (or mass), also known as the Law of Lomonosov-Lavoisier, states the following:
"In a chemical reaction the sum of the mass of the reactants is equal to the sum of the mass of the products."
Hence the famous phrase:
"The mass is not created or destroyed, it only transforms."
This was raised by the Russian scientist Mikhail Lomonosov in 1748 and independently discovered years later by the French chemist Antoine Lavoisier in 1785.
It should be noted that this principle is quite accurate for low-energy chemical reactions, but for nuclear reactions (collisions between particles at high energies), this classical definition does not apply (the total mass of the system does not have to be strictly conserved) and must be taken into account the equivalence between mass and energy that was postulated in Albert Einstein's theory of relativity:
"The amount of mass-energy that manifests a certain space-time is constant throughout the universe."
Being this expressed mathematically by his famous equation where he relates the energy [tex]E[/tex] with the mass [tex]m[/tex] and the speed of light [tex]c[/tex]:
[tex]E=mc^{2} [/tex]
Answer:
Matter cannot be created or destroyed.
Explanation:
APEX
When Anna eats an apple, the sugars in that apple are broken down into the substance called glucose. Glucose is then burned in her body for energy. One of the body parts that needs this energy is the heart, which beats due to electrical impulses. A byproduct of this glucose breakdown is the heat that warms her body and is later released. Which identifies the energy transformations that take place in Anna’s body as this process takes place? Mechanical energy is converted to kinetic energy, which is then converted to potential energy. Chemical energy is converted to thermal energy and electrical energy. Electrical energy is converted to chemical energy and thermal energy. Mechanical energy is converted to potential energy which is then converted to kinetic energy.
Answer:
Chemical energy is converted to thermal energy and electrical energy.
Explanation:
The sugar present in the apple is broken down into Glucose. This is chemical energy stored in the apple which is broken down into energy which is utilized by body for everyday works. The chemical energy gets converted to thermal energy which warms the body and electrical energy due to which the heart beats.
Answer:
Chemical energy is converted to thermal energy and electrical energy.
Explanation:
In Millikan’s experiment, the oil droplets acquire one or more negative charges by combining with the negative charges that are produced from the ionization of air by X rays. By measuring the charges on the oil droplets, he calculated the charge on a single electron as −1.60×10−19 C. The charge on any negatively charged oil droplet is always a whole-number multiple of the fundamental charge of a single electron.If Millikan was measuring the charge on an oil droplet with 10 negatively charged electrons on it, what charge would he have measured on the droplet?
Answer:
[tex]-1.6\cdot 10^{-18}C[/tex]
Explanation:
The charge of a single electron is:
[tex]q=-1.6\cdot 10^{-19}C[/tex]
If the oil droplet has N electrons, the total charge of the droplet will be
[tex]Q=Nq[/tex]
In this case, we have
N = 10
Therefore, the total charge on the droplet is
[tex]Q=(10)(-1.6\cdot 10^{-19} C)=-1.6\cdot 10^{-18}C[/tex]
In Millikan's experiment, the charge on any negatively charged oil droplet is always a whole-number multiple of the fundamental charge of a single electron. If the oil droplet had 10 negatively charged electrons, Millikan would have measured a charge of [tex]-1.60x10^-18[/tex] let.
Explanation:Millikan's experiment involved measuring the charges on oil droplets that acquire negative charges by combining with the negative charges produced from the ionization of air by X rays. Millikan found that the charge on any negatively charged oil droplet is always a whole-number multiple of the fundamental charge of a single electron, which is [tex]-1.60x10^-19[/tex]
If Millikan was measuring the charge on an oil droplet with 10 negatively charged electrons on it, he would have measured a charge of[tex]-1.60x10^-19[/tex] y 10, which is [tex]-1.60x10^-18[/tex]
What is the most common fuel used in nuclear power plants
Answer:
Uranium
Explanation:
The nuclear power plants on Earth work based on the principle of nuclear fission.
Nuclear fission occurs when a heavy unstable nucleus splits into lighter nuclei: in this process, the total mass of the final product is smaller than the mass of the initial heavy nucleus, so part of the mass is converted into energy according to Einstein's equation:
[tex]E=mc^2[/tex]
where E is the energy released when an amount of mass m is converted (c is the speed of light).
Generally, the "fuel" (the initial heavy unstable element) used in nuclear power plants is uranium. A nucleus of uranium is bombarded with slow neutrons, which cause the process of nuclear fission to start: the nucleus of uranium split into lighter nuclei, releasing also additional neutrons, which are used to start further nuclear reactions.
You are driving your small, fuel-efficient car when you have a head-on collision with a big, fuel-efficient truck that is three times as massive as your car. Head-on means, for example that if you are traveling in the positive x direction, the truck is traveling in the negative x direction. Right before the collision, you were traveling at a speed of 3.0 m/s and right after the collision, both vehicles are at rest. Due to the conservation of the momentum, you can find the speed of the truck before the collision. What was the kinetic energy of the truck Ktruck before the collision when the kinetic energy of the car was Kcar
Explanation:
Momentum before = momentum after
mv + MV = 0
(m) (3.0 m/s) + (3m) (V) = 0
V = -1.0 m/s
The truck was moving at 1.0 m/s before the collision.
The kinetic energy of the car was:
KE = 1/2 m v²
Kcar = 1/2 m (3.0)²
Kcar = 9/2 m
Ktruck = 1/2 M V²
Ktruck = 1/2 (3m) (1.0)²
Ktruck = 3/2 m
Ktruck = 1/3 Kcar
So the truck had 1/3 the kinetic energy of the car.
A sealed bottle is full of air. The volume of the bottle is decreased, but the temperature remains constant. What other change occurs in the bottle?
Answer:
The air pressure will increase.
Explanation:
Answer:The pressure of the gas in the bottle increases
Explanation:this is governed by Boyles law which states that at constant temperature,the volume of a gas is inversely proportional to it's pressure ,i.e mathematically V&1/P at constant temperature,this can be further arranged as P1V1=P2V2.the implication of this formula is that as volume of gases increases,it pressure is decreasing and vice versa.
It is important to note that the constant here is the absolute temperature of the bottle
two cars collide at an intersection. one car has a mass of 900 kg and is moving 10 m/s to the north, while the other has a mass of 1000 kg and is moving 7 m/s to the south. what is their combined momentum?
Answer:
2000 kgm/s to the north.
Explanation:
For any colliding bodies, momentum must be conserved.
In this case we are required to find the momentum before collision.
Since the two cars are moving to different direction, we are going to take one velocity as negative.
∴ (900×10) + (1000× -7) = 9000 + - 7000
= 9000 - 7000
= 2000 kgm/s
Since the answer is positive and we had taken the velocity due north as positive, the combined momentum is 2000 kgm/s to the north.
A hockey puck is set in motion across a frozen pond. If ice friction and air resistance are neglected, the force
required to keep the puck sliding at constant velocity is
A) the weight of the puck divided by the mass of the puck.
B) the mass of the puck multiplied by 9.8 meters per second per second.
C) qual to the weight of the puck.
D) zero newtons.
E) none of these.
Answer:
D) Zero newtons
Explanation:
According to the First Newton Law:
"An object keeps its state of rest or its state of uniform motion at constant velocity, when the net force acting on the object is zero"
In this problem, the hockey puck is initially set in motion. While in motion, there are no ice friction and air resistance acting on it: this means that the net force acting on it is zero, so there is no need for an additional force to keep the puck in its state of uniform motion at constant velocity, according to the abovementioned law.
Therefore, the correct answer is
D) zero newtons
In line with Newton's First Law of Motion, the force required to keep a hockey puck sliding at constant velocity on a frictionless surface is zero newtons, because it moves at a constant velocity unless acted upon by an unbalanced force.
Explanation:The answer is D) zero newtons. According to Newton's First Law of Motion, an object will continue to move at a constant velocity unless acted upon by an unbalanced force. When the hockey puck is in motion on a frictionless surface, it keeps moving at a steady velocity without the need for an additional force. The net force acting on the puck is zero. Thus, no extra force is required to maintain its constant velocity.
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What is the energy of a photon that has the same wavelength as an electron having a kinetic energy of 15 ev?
Answer: [tex]6.268(10)^{-16}J[/tex]
Explanation:
The kinetic energy of an electron [tex]K_{e}[/tex] is given by the following equation:
[tex]K_{e}=\frac{(p_{e})^{2} }{2m_{e}}[/tex] (1)
Where:
[tex]K_{e}=15eV=2.403^{-18}J=2.403^{-18}\frac{kgm^{2}}{s^{2}}[/tex]
[tex]p_{e}[/tex] is the momentum of the electron
[tex]m_{e}=9.11(10)^{-31}kg[/tex] is the mass of the electron
From (1) we can find [tex]p_{e}[/tex]:
[tex]p_{e}=\sqrt{2K_{e}m_{e}}[/tex] (2)
[tex]p_{e}=\sqrt{2(2.403^{-18}J)(9.11(10)^{-31}kg)}[/tex]
[tex]p_{e}=2.091(10)^{-24}\frac{kgm}{s}[/tex] (3)
Now, in order to find the wavelength of the electron [tex]\lambda_{e}[/tex] with this given kinetic energy (hence momentum), we will use the De Broglie wavelength equation:
[tex]\lambda_{e}=\frac{h}{p_{e}}[/tex] (4)
Where:
[tex]h=6.626(10)^{-34}J.s=6.626(10)^{-34}\frac{m^{2}kg}{s}[/tex] is the Planck constant
So, we will use the value of [tex]p_{e}[/tex] found in (3) for equation (4):
[tex]\lambda_{e}=\frac{6.626(10)^{-34}J.s}{2.091(10)^{-24}\frac{kgm}{s}}[/tex]
[tex]\lambda_{e}=3.168(10)^{-10}m[/tex] (5)
We are told the wavelength of the photon [tex]\lambda_{p}[/tex] is the same as the wavelength of the electron:
[tex]\lambda_{e}=\lambda_{p}=3.168(10)^{-10}m[/tex] (6)
Therefore we will use this wavelength to find the energy of the photon [tex]E_{p}[/tex] using the following equation:
[tex]E_{p}=\frac{hc}{lambda_{p}}[/tex] (7)
Where [tex]c=3(10)^{8}m/s[/tex] is the spped of light in vacuum
[tex]E_{p}=\frac{(6.626(10)^{-34}J.s)(3(10)^{8}m/s)}{3.168(10)^{-10}m}[/tex]
Finally:
[tex]E_{p}=6.268(10)^{-16}J[/tex]
Light amplification by stimulated emission of radiation is the full meaning of the acronym _________
Answer: LASER (Light Amplification by Stimulated Emission of Radiation)
A laser is a device that works by the principles of optics that emits a monochromatic light beam (of a single wavelength), coherent and with high intensity. Being this possible thanks to the electrical or thermal stimulation of atoms of a specific material and, on which the color of the emitted light will depend.
Basically, this instrument concentrates the light in a narrow beam and emits it in a concentrated and coherent form.
Where is visible light located on the electromagnetic spectrum
Answer:
The portion visible by the human eye of the electromagnetic spectrum is between 380 nm (violet-blue) and 780 nm (red) approximately.
This part of the spectrum is located between ultraviolet light and infrared light.
It should be noted that the fact only part of the whole electromagnetic spectrum is visible to humans is because the receptors in our eyes are only sensitive to these wavelengths.
Answer:
near the middle
Explanation:
for gradpoint anyway
The alpha particles leave visible tracks in the cloud chamber because
Ionization by the alpha particle seeds the formation of clouds where the particle has passed.
The kinetic energy of the alpha particles heats the air.
The alpha particle is so energetic that it leaves a smoke trail behind.
The alpha particle strikes nitrogen molecules and breaks them into atomic nitrogen.
The inner atmosphere of a cloud chamber is composed of an easily ionizable gas, this means that little energy is required to extract an electron from an atom. This gas is maintained in the supercooling state, so that a minimum disturbance is enough to condense it in the same way as the water is frozen.
Then, when a charged particle with enough energy interacts with this gas, it ionizes it.This is how alpha particles are able to ionize some atoms of the gas contained inside the chamber when they cross the cloud chamber.
These ionized atoms increase the surface tension of the gas around it allowing it to immediately congregate and condense, making it easily distinguishable inside the chamber like a small cloud. In this way, it is perfectly observable the path the individual particles have traveled, simply by observing the cloud traces left in the condensed gas.
Planet that has an orbit that intersects the orbit of pluto
Answer:
Neptune
Explanation:
"Answer: Pluto is usually farthest from the Sun. However, its orbit "crosses" inside of Neptune's orbit for 20 years out of every 248 years. Pluto last crossed inside Neptune's orbit on February 7, 1979, and temporarily became the 8th planet from the Sun. "
Source:https://starchild.gsfc.nasa.gov/docs/StarChild/questions/question5.html
A friend asks you how much pressure is in your car tires. You know that the tire manufacturer recommends 30 psi, but it's been a while since you've checked. You can't find a tire gauge in the car, but you do find the owner's manual and a ruler. Fortunately, you've just finished taking physics, so you tell your friend, "I don't know, but I can figure it out." From the owner's manual you find that the car's mass is 1550 kg. It seems reasonable to assume that each tire supports one-fourth of the weight. With the ruler you find that the tires are 16 cm wide and the flattened segment of the tire in contact with the road is 14 cm long. What answer will you give your friend?
Answer:
25 psi
Explanation:
The weight of the car is:
W = mg
W = 1550 kg * 9.8 m/s²
W = 15,190 N
Divided by 4 tires, each tire supports:
F = W/4
F = 15,190 N / 4
F = 3797.5 N
Pressure is force divided by area, so:
P = F / A
P = (3797.5 N) / (0.16 m × 0.14 m)
P ≈ 170,000 Pa
101,325 Pa is the same as 14.7 psi, so:
P ≈ 170,000 Pa × (14.7 psi / 101,325 Pa)
P ≈ 25 psi
The pressure in each tire is ≈ 25 psi which falls within the recommended manufacturer pressure
Given data ;
mass of car ( m ) = 1550 kg
width of tires ( w ) = 16 cm = 0.16 m
length of tires ( l ) = 14 cm = 0.14 m
First step : Determine the Total weight of car
W = m*g ---- ( 1 )
= 1550 * 9.8 = 15,190 N
∴ Weight supported by each tire = ( W / 4 )
= 15,190 / 4 = 3797.5 N
Final step : determine the Pressure in the tires
P = F / A -------- ( 2 )
F ( force ) = 3797.5 N
A ( area ) = 0.14 * 0.16 = 0.0224
back to equation ( 2 )
P = 3797.5 / 0.0224
≈ 170,000 Pa
∴ Pressure in each tire ≈ 25 psi
Hence we can conclude that the pressure in each tire is ≈ 25 psi.
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When the flashlight is in the air and the refracted ray enters the water, how does the angle of refraction compare with the angle of incidence?
Answer:
The refracted angle will be less than the angle of incidence and the speed of light is slower in the new medium (which is water) and is closer to the normal.
Try remembering this by using FST SFA (Fast Sofa)
Fast -> Slow = Towards the normal
Slow -> Fast = Away from normal
When the flashlight is in the air and the refracted ray enters the water, the angle of refraction will be less than the angle of incidence.
What is refracted ray?When the light ray falls on the surface with angle of incidence, the lights gets reflected in the same medium with angle of reflection. The remaining rays gets into the medium on the other side of the surface.
The refracted angle is always less than the angle of incidence and the speed of light is slower comparatively in the another medium.
Thus, when the flashlight is in the air and the refracted ray enters the water, the angle of refraction will be less than the angle of incidence.
Learn more about refracted ray.
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A small planet having a radius of 1000 km exerts a gravitational force of 100 N on an object that is 500 km above its surface. If this object is moved 500 km farther from the planet, the gravitational force on it will be closest to :(A) 75 N(B) 71 N(C) 56 N(D) 50 N(E) 25 N
Answer:
56 N
Explanation:
Gravitational force on the object:
[tex]F = G\frac{Mm}{d^2}[/tex]
where, G is the gravitational constant, M is the mass of the planet and m is the mass of the object, d is the distance between the planet and the object.
[tex]F \times d^2= GMm\\ \Rightarrow GMm= (100)(1.5\times10^6)^2[/tex]
d'=d+500 km
[tex]F'=\frac{(100)(1.5\times10^6)^2}{(2\times10^6)^2} = 56.25N[/tex]
Thus, option (c) is correct.
The new gravitational force on the object, when moved 500km farther from the planet, will be closest to 56N. This result is calculated using inverse square law of gravity where the gravitational force decreases with the square of the increase in distance.
Explanation:The physics concept at work here is the inverse square law of gravity, which states that the gravitational force between two objects decreases with the square of the distance between them. In mathematical terms, it is written as F = G*((m1*m2)/r^2), where F is the force of gravity, G is the gravitational constant, m1 and m2 are the masses of the two objects, and r is the distance between the centers of the two objects.
In this case, the radius of the planet is 1000 km and the object is 500 km above the surface of the planet, so the total distance (r) is 1500 km. When the object is moved 500 km farther, the new distance will be 2000 km or 4/3 times the original distance. This factor squared is 16/9, so the new gravitational force will be 9/16 of the original force. Therefore, the new gravitational force is 9/16 * 100 N = 56.25 N, so the closest choice is (C) 56 N.
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A typical american family uses 1000 kwh of electricity a month. what is the average rrns current in the 120 v power line to a typical house?
Power = (1000 kilo-Watt-hr/mo) x (1000/kilo) x (mo/30day) x (day/24 hr)
Power = (1000 x 1000 / 30 x 24) (kilo-watt-hr-mo-day/mo-kilo-day-hr)
Power = (1,000,000/720) watt
(voltage x current) = (1,000,000/720) watts
120v x current = (1,000,000/720) watts
Current = 1,000,000 / (720 x 120) Amperes
Current = 11.57 Amperes
The typical American home draws around an average effective (RMS) current of 11.58 amps from a 120 V power line.
Explanation:The average current in the power line of a typical American house can be calculated using Ohm's law and the power equation. If a typical American family uses 1000 kWh per month, we need to convert this to average power in kW, which gives (1000 kWh) / (30 days*24 hours) = 1.39 kW = 1390 W.
Given that the voltage is 120 V, we can use the formula: P = IV, rearranging to find I = P/V. Therefore, I = 1390 W / 120 V = 11.58 A.
This means the power to a standard American home running at typical usage rates should draw an average effective(RMS) current of around 11.58 amps from a 120 V power line.
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The visible light spectrum ranges between
Answer: 380 nm (violet-blue) and 780 nm (red)
Explanation:
The portion visible by the human eye of the electromagnetic spectrum is between 380 nm (violet-blue) and 780 nm (red) approximately.
This part of the spectrum is located between ultraviolet light and infrared light.
It should be noted that the fact only part of the whole electromagnetic spectrum is visible to humans is because the receptors in our eyes are only sensitive to these wavelengths.
Red goes in the first blank and violet goes in the second blank if you're using plato
what is the magnification of a virtual image if the image is 10.0 cm....
Answer:
5.0
Explanation:
because 50.0 / 10.0 equals 5
A student pushes a 35-kg block on a frictionless, horizontal surface with a force of 18 N. What is the acceleration of the block ?
A. 1.0m/sSquared
B. 1.4m/sSquared
C. 1.6m/sSquared
D. 1.9m/sSquared
Newton wrote . . . F = m a
From that, we can derive . . . a = F/m
a = (18 N) / (35 kg)
a = 0.514... m/s^2
None of the choices says this.
Choice-D is the reciprocal of the correct answer ... the result of doing the division backwards ... m/F .
A roller coaster car rapidly picks up speed as it rolls down a slope. As it starts down the slope, its speed is 4m/s. But 3 seconds later at the bottom of the slope its speed is 22m/s. What is its average acceleration?
Answer:
6 m/s^2
Explanation:
The average acceleration of the car is given by:
[tex]a=\frac{v-u}{t}[/tex]
where
v is the final speed
u is the initial speed
t is the time elapsed
For the car in this problem,
v = 22 m/s
u = 4 m/s
t = 3 s
Therefore, the acceleration of the car is
[tex]a=\frac{22 m/s-4 m/s}{3 s}=6 m/s^2[/tex]
How many calories are required to raise the temperature of 105 g of water from 30.0°c to 70.0°c?
Let's start by explaining that 1 Calorie ([tex]1 cal[/tex]) is defined as a unit of thermal energy that is equivalent to the amount of heat ([tex]Q[/tex]) needed to raise the temperature of 1 gram [tex]1g[/tex] of water by 1 degree Celsius [tex]1\°C[/tex].
The formula to calculate it is:
[tex]Q=m. c. \Delta T[/tex] (1)
Where:
[tex]m[/tex] is the mass
[tex]c[/tex] is the specific heat of the element. In the case of water [tex]c=1cal/g[/tex]
[tex]\Delta T[/tex] is the variation in temperature, which in this case is [tex]\Delta T=70\°C-30\°C=40\°C[/tex]
Rewriting equation (1) with the known values:
[tex]Q=(105g)(1 cal/g)(40\°C)[/tex]
[tex]Q=4200 cal[/tex]
The minimum energy required for an effective collision is called
Answer:
Activation Energy
Explanation:
Effective collisions are those that result in a chemical reaction. In order to produce an effective collision, reactant particles must possess some minimum amount of energy. This energy, used to initiate the reaction, is called the activation energy.
Which of the following statements are true concerning a stable nucleus?Check all that apply..There is a limit to the size of a stable nucleus because of the short range of the strong nuclear force.A stable nucleus contains a larger number of neutrons than protons.There is no limit to the size of a stable nucleus because of the great strength of the strong nuclear force.A stable nucleus contains nearly equal numbers of protons and neutrons.A stable nucleus contains a larger number of protons than neutrons.
Answer:
There is a limit to the size of a stable nucleus because of the short range of the strong nuclear force
A stable nucleus contains nearly equal numbers of protons and neutrons
Explanation:
For an atom nucleus to be stable it has to have a balance between the strong nuclear forces keeping the protons and neutrons together against the repulsive electrostatic forces of the positively charged protons. When the nucleus is too large, the binding energy of the strong nuclear forces, that act over a short range, may not be sufficient to hold the nucleus together hence causing instability.