a 5.00 kg ball, moving to the right at a velocity of 2.00 m/s on
the frictionless table, collide head on with a stationary 7.50 kg
ball. find the final velocities of the balls if the collision is
elastic, completely inelastic the balls stick together
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A thermos bottle in the shape of a cylinder has an inner radius of 4.0 cm, an outer radius of 4.5 cm, and a lengt of 30cm. The insulating walls have a thermal conductivity equal to 2.0 x 10^-5 cal/(sec-cm celsius). One liter of hot coffee at 90 degrees Celsius is poured into the bottle. If the outside wall remains at 20 degrees Celsius, how long does it take for the coffee to cool to 50 degrees Celsius?
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The motion of a human body through space can be modeled as the motion of a particle at the body's center of mass as we will study in a later chapter. The components of the displacement of an athlete's center of mass from the beginning to the end of a certain jump are described by the equations
xf = 0 + (10.8 m/s)(cos 18.5
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If the coefficient of kinetic friction between tires and dry pavement is 0.75, what is the shortest distance in which you can stop an automobile by locking the brakes when traveling at 25.5 m/s ?
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A projectile is launched with an initial speed of 40.0 m/s at 60.0 degrees above the horizontal. It hits the ground at the same height it was launched from. Neglect air resistance.
a) What is the projectile's smallest speed as it moves through air?
b) What is the projectile's smallest magnitude of acceleration as it moves through air?
c) What is the projectile's speed 1.00 second after launch?
d) What is the magnitude of the projectile's displacement 1.00 second after launch?
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Two ice skaters, Daniel (mass 65.0 kg ) and Rebecca (mass 45.0 kg ), are practicing. Daniel stops to tie his shoelace and, while at rest, is struck by Rebecca, who is moving at 14.0 m/s before she collides with him. After the collision, Rebecca has a velocity of magnitude 8.00 m/s at an angle of 53.1 ∘ from her initial direction. Both skaters move on the frictionless, horizontal surface of the rink. |
Part A What is the magnitude of Daniel's velocity after the collision?
SubmitMy AnswersGive Up Part B What is the direction of Daniel's velocity after the collision?
SubmitMy AnswersGive Up Part C What is the change in total kinetic energy of the two skaters as a result of the collision? |
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Why is it hard to measure the phenomenon experienced at the speed of light?
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An electron that has an energy of approximately 3.0e+02 eV moves between rigid walls 0.6 nm apart.
(a) Find the quantum number n for the energy state that
the electron occupies.
_____________
(b) Find the precise energy of the electron.
_____________eV
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a.)A 9 m ladder whose weight is 417 N is placed against a smooth vertical wall. A person whose weight is 846 N stands on the ladder a distance 3.4 m up the ladder. The foot of the ladder rests on the floor 1.98 m from the wall. Calculate the force exerted by the wall. Answer in units of N.
b.)Calculate the notmal force exerted by the wall. Answer in units of N.
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Some people are able to spin a basketball on the tip of a finger. It is often done by balancing the ball on the tip of the finger and brushing the other hand along the side of the ball to cause it to rotate. Suppose the ball begins from rest and reaches a final angular speed of 20.15 rad/s in 1.55 s.
(a) Assuming the ball is subject to a constant angular acceleration, what is the magnitude of the constant angular acceleration? rad/s2
(b) Through how many revolutions does the ball rotate during the 1.55 s?
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coil has 30 turns and carries current. The cross sectional area of the coil is 7.5cm. At a point located on the axis of the coil at a distance 1.5m, the magnetic field os 0.2mG, what is current in the coil?
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When the tail light of a car is turned on, 0.5 A flows through the wires. The length of one wire from the battery to the tail light is 5.0 meters.Estimate how long you think it will take an electron to travel from the battery to the tail light and how many electrons flow through the tail in one minute. Thank you!
Given :
14AWG copper wire is used, which has a cross sectional area of 2.1e-6 m^2
2 The density of copper is 8.96 grams/cm^3
3 The atomic mass of copper is 63.5.
Each copper atom has one free electron.
(should be 3.3 days and 1.9e20 electrons per minute. How? ) Please show each steps. Thank you so much!
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A 2.8kg balloon is filled with helium ( density = 0.179 kg/m 3 ).
Part A
If the balloon is a sphere with a radius of 5.1m , what is the maximum weight it can lift? (N)
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A spring contains a weight of 32 lbs. It is stretched to a
distance of 1.6 ft and is
currently at rest. The damping force is 9 ˙x and an external force
of 2 cos 4t
applied. Set up the differential equation,
including the initial conditions, but
you do not need to solve.
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