A bicycle wheel can be thought of simply as a central solid cylinder (the part that attaches to the axle) surrounded by a thin shell of mass (the rim and tire) located along the outer edge of the wheel. Compared to these parts of the wheel, the mass of the spokes is small enough to be neglected. A sample bicycle wheel has mass 2.0 kg, half of which is in the central cylinder. The other half is in the rim and tire. The central cylinder has a radius of 4.0 cm (note the unit!). The wheel has a radius of 40.0 cm.
a) What is the moment of inertia of the central cylinder?
b) What is the moment of inertia of the rim/tire? Hint: you should not be using the same equation you used in (a).
c) The moment of inertia of the entire wheel is just the sum of the individual moments of inertia of the parts. What is the moment of inertia of the wheel?
The wheel described above rolls down a ramp without slipping. It starts rolling on the ramp at a point where the ramp is 2.0 m above the ground. Any energy lost to frictional effects as the wheel rolls is negligible.
d) What gravitational potential energy (relative to the ground) does the wheel have at the top of the ramp?
e) What types (plural!) of mechanical energy does the wheel have when it reaches the ground?
f) How fast is the wheel moving at the bottom of the ramp? Hint: This is asking for the translational velocity of the wheel. You need to set up an energy conservation equation in which you can isolate the translational velocity as the only unknown quantity.
g) Assuming acceleration is constant, what is the average translational velocity of the wheel as it rolls down the ramp? Hint: since the wheel started from rest, the relationship between the average velocity and the velocity at the bottom of the ramp is quite simple; go back to your kinematics equations!
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A 2.7 kg block with a speed of 5.4 m/s collides with a 5.4 kg block that has a speed of 3.6 m/s in the same direction. After the collision, the 5.4 kg block is observed to be traveling in the original direction with a speed of 4.5 m/s. (a) What is the velocity of the 2.7 kg block immediately after the collision? (b) By how much does the total kinetic energy of the system of two blocks change because of the collision? (c) Suppose, instead, that the 5.4 kg block ends up with a speed of 7.2 m/s. What then is the change in the total kinetic energy?
Part a: 3.6 m/s
Part b: -2.19 J
I can not figure out part c.
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Describe and explain the optics of the microscope and the telescope.
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Can you explain the major concepts needed to launch a satellite into space, place it in a particular orbit around the Earth, keep it in that orbit, and eventually dispose of it?
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Consider a series of 8 flips of a fair coin.
Calculate the probabilities for obtaining 0-8 heads. We will consider each of these nine outcomes to be macrostates of the system. Graph these probabilities below.
ProbabilityNumber of Heads0123456780.000.030.050.080.100.130.150.170.200.220.250.270.300.330.350.380.40
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Extract the radial part of the Schrodinger. wave equation in spherical coordinates for a hydrogen like atom. Use the methods of eigenvalues. Plot the results with the radial wave function as a function of the distance from the nucleus r.
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A soccer ball (mass = 0.450 kg, diameter = 0.70 m) is rolled down a 3.0 m high ramp that makes an angle of 30 degrees with the horizontal and is 6.0 m long. Assume the ball is a hollow sphere (I = 2/3MR^2) and begins at rest. How long (in seconds) would it take the ball to reach the bottom of the ramp?
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List the recommendation of federal, state and local regulations regarding radiation protection requirements relating to the assignment of personal monitoring devices.
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How does the physics learned in the classroom compare to physics in the real world? Provide a detailed response.
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A 3.4 kg box rests on a 17 degree inclined plane. How much of its weight is pulling it down the ramp? How much of its weight is directed perpendicularly to the ramp?
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What does impulse do to an object? How does a large impulse affect an object differently Than a small one?
Use what you said above to answer: What does the presence of an airbag do to a person's head during an automobile collision? Answer in terms of impulse, impact, force, and time using complete sentences.
So finally in terms of impulse and momentum, why do airbags make automobiles safer?
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In Anchorage, collisions of a vehicle with a moose are so common that they are referred to with the abbreviation MVC. Suppose a 950 kg car slides into a stationary 550 kg moose on a very slippery road, with the moose being thrown through the windshield (a common MVC result). (a) What percent of the original kinetic energy is lost in the collision to other forms of energy? A similar danger occurs in Saudi Arabia because of camel–vehicle collisions (CVC). (b) What percent of the original kinetic energy is lost if the car hits a 310 kg camel? (c) Generally, does the percent loss increase or decrease if the animal mass decreases?
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Use Ge = 9.8 m/s and Gm = Ge/6 for the Earth and Moon’s acceleration of gravity.
1. What is the apparent weight (or force on the scale from
the
person) of this 60 kg person in this elevator with the
following
locations and accelerations?
(a) On Earth accelerating up at 9.8 m/s
(b) On the Moon accelerating up at 9.8 m/s
(c) On Earth accelerating down at 9.8 m/s
(d) On the Moon accelerating down at 9.8 m/s
Also describe what is going on in parts (c) and (d).
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If a satellite is in a sufficiently low orbit, it will encounter air drag from the earth's atmosphere. Since air drag does negative work (the force of air drag is directed opposite the motion), the mechanical energy will decrease. If E decreases (becomes more negative), the radius r of the orbit will decrease. If air drag is relatively small, the satellite can be considered to be in a circular orbit of continually decreasing radius.
a.) A satellite with mass 2250 kg is initially in a circular orbit a distance 285 km above the earth's surface. Due to air drag, the satellite's altitude decreases to 225 km . Calculate the initial orbital speed
b.) Calculate the increase in orbital speed.
c.) Calculate the initial mechanical energy.
d. ) Calculate the change in kinetic energy.
e.) Calculate the change in gravitational potential energy.
f.) Calculate the change in mechanical energy.
g.) Calculate the work done by the force of air drag.
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A Gaussian surface in the shape of a right circular cylinder with end caps has a radius of 16.4 cm and a length of 68.1 cm. Through one end there is an inward magnetic flux of 36.6 μWb. At the other end there is a uniform magnetic field of 1.40 mT, normal to the surface and directed outward. What are the (a) magnitude and (b) direction (inward or outward) of the net magnetic flux through the curved surface?
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