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 The definition of average velocity is

A student weighing 500 N stands on a bathroom scale in the school’s elevator. When 

the scale reads 520 N, the elevator must be 

An object moves to the East across a frictionless surface with constant speed. A person 

then applies a constant force to the North on the object. What is the resulting path that 

the object takes?

A toy car moves along the x-axis according to the velocity versus time curve shown to the right. When does the car have zero acceleration?

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In which one of the following situations is the net force constantly zero on the object?

What net force is necessary to keep a 1.0 kg puck moving in a circle of radius 0.5 m on a horizontal frictionless surface with a speed of 2.0 m/s? 

A large wedge rests on a horizontal frictionless surface, as shown. A block starts from rest and slides down the inclined surface of the wedge, which is rough. During the motion of the block, the center of mass of the block and wedge system

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A box slides to the right across a horizontal floor. A person called Ted exerts a force T to the right on the box. A person called Mario exerts a force M to the left, which is half as large as the force T. Given that there is friction f  and the box accelerates to the right, rank the sizes of these three forces exerted on the box.