A boy shoves his stuffed toy zebra, which has mass m, down a frictionless chute, starting at a height D above the bottom of the chute and with an initial speed of v. The toy animal emerges horizontally from the bottom of the chute and continues sliding along a horizontal surface with coefficient of kinetic friction μ. At what distance d from the bottom of the chute does the toy zebra come to rest? Express your answer in terms of the given variables and g, the acceleration due to gravity.
I thought the answer was (0.5v^2+gh)/(mu x g) but it is not correct apparently
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Blocks A (mass 5.00 kg ) and B (mass 9.00 kg ) move on a frictionless, horizontal surface. Initially, block B is at rest and block A is moving toward it at 2.00 m/s . The blocks are equipped with ideal spring bumpers. The collision is head-on, so all motion before and after the collision is along a straight line. Let +x be the direction of the initial motion of block A.
a.) Find the maximum energy stored In the spring bumpers.
b.) Find the velocity of block A when the energy stored in the spring bumpers is maximum.
c.) Find the velocity of block B when the energy stored in the spring bumpers is maximum.
d.) Find the velocity of block A after they have moved apart.
e.) Find the velocity of B after they have moved apart.
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Draw how the negative and positive charges are distributed for DC and AC plasmas
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A bullet of mass 0.010 kg and speed of 100 m/s is brought to rest in a wooden block
after penetrating a distance of 0.10 m. The work done on the bullet by the block is
A.
50 J.
B.
-
50 J.
C.
0.001 J.
D.
-
0.001 J.
E.
zero.
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A helium-filled balloon is attached to one en of a uniform wooden beam, lifting it partially up off of the ground. The beam is 2.25 meters long and it weighs 578N. What Volume of helium is required to hold the beam up at an angle of 30.00 ? (You can ignore the weight of the empty balloon and the wire connecting it to the beam.)
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2. As seen from Earth, two spaceships A and B are approaching along perpendicular directions. Spaceship A is observed by an Earth observer to have velocity uy = −0.60c and spaceship B to have a velocity ux = −0.80c. Find the magnitude of the relative velocity of the two spaceships by transforming the velocity of one ship into the rest frame of the other. Remember, the answer has to be less than c.
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Why does the weight of an object in the air differ from its weight in a vacuum (remembering that weight is the force exerted against a supporting surface)? Cite an example in which this would be an important consideration.
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3. A proton is accelerated in a Van de Graff through a potential difference of 4 million Volts.
a. What is its its total energy after acceleration?
b. What is the magnitude of its final momentum?
c. What is its velocity?
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A helium-filled balloon has a volume of 0.010 m3. The temperature in the room and in the balloon is 20 C What are the average speed of a particle of helium inside the balloon? What is the thermal energy of the helium in the balloon? Assume that due to stretching of the balloon the pressure inside it is 1.1 atm.
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A transverse traveling wave on a taut copper wire has an amplitude of 0.200 mm and a frequency of 500 Hz. It travels with a speed of 100 m/s.
(a) Write an equation in SI units of the form y = A sin (kx − ωt) for this wave. (Do not forget units in your answer.)
(b)Find the transverse velocity of the wire at the position x=0.500m at time t=1.00×10-3 s.
(c) The diameter of the wire is 1.00 mm, and the mass per unit volume for copper is 8.92 g/cm3 . Find the tension in the wire.
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A block of ice, mass 3.20 kg and initial temperature of -8 oC, is placed in an insulating container. 5.00 kg of water at temperature 13 oC, is added to the container. The water and ice exchange heat, but no other heat flows into or out of the container.
In the process of the water and ice reaching equilibrium, how much ice melts?
Give your answer in kg to three digits.
Note: It is possible that the answer is zero.
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A spacecraft of mass m=520 kg stationary with respect to the South Pole of the Earth runs out of fuel and starts to fall vertically toward the South Pole. If the initial altitude of the space craft is 800 km, what is the velocity of the space craft when it hits the surface of the Earth in km/s? Assume that you can ignore the atmospheric friction. Note that the universal gravitational constant G = 6.67x10-11 Nm2/kg2 , the radius of the Earth RE = 6.37x106 m, and the mass of the Earth ME = 5.97 x 1024 kg. (Hint: Conservation of energy).
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A thin rod (length = 1.85 m) is oriented vertically, with its bottom end attached to the floor by means of a frictionless hinge. The mass of the rod may be ignored, compared to the mass of the object fixed to the top of the rod. The rod, starting from rest, tips over and rotates downward. (a) What is the angular speed of the rod just before it strikes the floor? (Hint: Consider using the principle of conservation of mechanical energy.)(b) What is the magnitude of the angular acceleration of the rod just before it strikes the floor?
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Determine the minimum and maximum impact parameters bmin and bmax for the classical derivation of charged particle collisional stopping power. Explain the physical meaning of each.
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