A sphere with radius R has a charge density given by
ρ = cr3.
Use Gauss's law to find an expression for the magnitude of the electric field at a distance r from the center of the sphere, where we have the following. (Use the following as necessary: c, r, R, and ε0. Assume c is positive.)
(a)
r < R
E =
(b)
r > R
E =
In: Physics
1.A moving ball(1) collides elastically with an identical stationary ball (2). Ball(2) shoots off to the right along the x axis. What is the final velocity of ball(1) and the final speed of ball (2)?
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2.a massless rigid rod with x1=0, m1=6kg, x2=1, m2=2kg
a.what is xc the centre of mass?
b.A force 8*10^10Ng^ (upward) hits m2 for deltaT=10^-10s.
the instant after, what is the final velocity of m2?
c.what is the final velocity of the center of mass and the final angular velocity about the centre of mass?
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Two particles, m1 = 2m and m2 = m, are suspended on massless cords of the same length l = 1.00 m so that they touch each other (see Fig. below). Particle 1 is displaced to an angle of 30
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How do I convert 29.35 W to J/sec?
How do I convert 312 ft3s-1mi-2 to m3 min.-1km-2?
How do I convert from 2.2 km/hr to ft sec-1 and mi2 hr-1?
How do I convert from 5.4 ft sec-1 to cm sec-1 and m hr-1?
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Two train cars are on a straight, horizontal track. One car starts at rest and is put in motion with a constant acceleration of 1.48 m/s2. This car moves toward a second car that is 21.40 m away and moving at a constant speed of 3.79 m/s.
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A 10.0 cm tall pencil stands balanced on its eraser, 25.0 cm in front of a mirror with radius of curvature of 1.00 m. Where will the image form, and how tall will the image be, if a) the mirror is concave, and b) the mirror is convex?
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A small block with mass 0.0450kg slides in a vertical circle of radius 0.575m on the inside of a circular track. During one of the revolutions of the block, when the block is at the bottom of its path, point A, the magnitude of the normal force exerted on the block by the track has magnitude 3.85N . In this same revolution, when the block reaches the top of its path, point B, the magnitude of the normal force exerted on the block has magnitude 0.685N .
How much work was done on the block by friction during the motion of the block from point A to point B?
Express your answer with the appropriate units.
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Can a piece of adhesive tape hold an electric charge? If so, will the charge be positive or negative? Can a predication be made of which material will be positive and which negative if any two insulators are rubbed together?
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Blocks A (mass 3.50 kg ) and B (mass 8.00 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.
Find the maximum energy stored in the spring bumpers.
Find the velocity of block A when the energy stored in the spring bumpers is maximum.
Find the velocity of block B when the energy stored in the spring bumpers is maximum.
Find the velocity of block A after they have moved apart.
Find the velocity of B after they have moved apart.
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PLEASE DONT ROUND ANYTHING KEEP ALL DECIMALS
A 32.5 kg box initially at rest is pushed 4.10 m along a rough, horizontal floor with a constant applied horizontal force of 145 N. If the coefficient of friction between box and floor is 0.300, find the following.
(a) the work done by the applied force
J
(b) the increase in internal energy in the box-floor system due to
friction
J
(c) the work done by the normal force
J
(d) the work done by the gravitational force
J
(e) the change in kinetic energy of the box
J
(f) the final speed of the box
m/s
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Construct an energy level diagram for a doubly-ionized Lithium atom (z=3, 1 electron). What are the possible frequencies of light emitted for the electron moving around between the first three energy levels? (there are three answers)
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A billiard ball of mass m = 0.25 kg strikes the cushion of a billiard table at ?1 = 50
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Circular Motion, Kinetic Energy, Work and Power
Wind energy is the fastest growing renewable energy source, the US has a goal of producing 20 percent of it’s electricity from wind by 2030. All of our energy options come with a set of pros and cons of varying degrees. One concern, which is minor unless it lands on your house, with wind turbines is ice throw off from the tips of the blade. Consider a 50 meter radius wind turbine (about 3 MW) rotating clockwise 15 times a minute with a hub height of 150 meters. Calculate the following for a 100 kg piece of ice at the tip of the turbine blade (r=50m):
a) The angular velocity of the rotating blades in radians per second, the period, or time it takes for a rotor blade to make one revolution and the frequency, or number of rotations made in one second.
b) The magnitude of the force required at the top circular path to keep the piece of ice in circular motion.
c) The magnitude of the force required at the bottom of the circular path to keep the piece of ice in circular motion.
d) The range or distance the piece of ice would travel if it was released at the highest point in the rotation. Consider clockwise rotation so the ice lands in the positive x direction.
e) The kinetic energy of the piece of ice upon release.
f) The kinetic energy of the piece of ice upon landing.
g) The work done by the gravitational force from release to landing.
h) Is this the maximum range? Is this the most likely point of release? Briefly explain your reasoning.
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2. Describe the difference between a material that is strong vs. a material that is tough. Draw an example of the stress-strain curve of each.
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