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A rocket moves through empty space in a straight line with constant speed.  It is far from the gravitational effect of any star or planet.  Under these conditions, the force that must be applied to the rocket in order to sustain its motion is

The kinetic energy of a motorcycle and rider is 60,000 J. If  their total  mass is 300 kg, what is their speed?    

Suppose that Paul D. Trigger fires a bullet from a gun. The speed of the bullet leaving the muzzle will be the same as the speed of the recoiling gun ____.

A flywheel of radius 25.0 cm is rotating at 655 rpm. Find the linear speed ( in m/s ) of a point on the rim.

A freight car moves along a frictionless level railroad track at constant speed.  The car is open on top.  A large load of coal is suddenly dumped into the car.  What happens to the velocity of the car?

What type of acceleration does an object moving with constant speed in a circular path experience?

A teenager pushes tangentially on a small hand-driven merry-go-round and is able to accelerate it from rest to a frequency of 15 rpm in 10.0 s. Assume the merry-go-round is a uniform disk of radius 2.5 m and has a mass of 760 kg. Calculate the torque required to produce the acceleration, neglecting frictional torque.

The difference between impulse and impact force involves the

A job is done slowly, and an identical job is done quickly. Both jobs require the same amount of ____, but different amounts of ____. Pick the two words which fill in the blanks in their respective order.

A contestant in a winter games event pulls  a 30.0-kg block of ice across a frozen lake with a force of 25 N at 32.0° above the horizontal  and it moves with an acceleration of 0.710 m/s2 to the right. (a) What is the normal force exerted by the lake surface on the block of ice?