Suppose that an object is moving with constant nonzero acceleration. Which of the following is an accurate statement concerning its motion?
In equal time its velocity changes by equal amounts
If a force always acts perpendicular to an object's direction of motion, that force cannot change the object's kinetic energy.
A 3 kg. ball swings rapidly in a complete vertical circle of radius 2 m by a light string that is fixed at one end. The ball moves so fast that the string is always taut and perpendicular to the velocity of the ball. As the ball swings from its lowest point to its highest point.
work done by gravity is -118 and work done by tension in string is zero
An apple is sitting on a table. Identify the action-reaction pair.
Action: force of gravity on the apple;
Force on the center of the earth from the apple
A box slides down a frictionless plane inclined at an angle theta, above the horizontal. The gravitational force on the box is directed
A box of mass m is pressed against (but is not attached to) an ideal spring of force constant k and negligible mass, compressing the spring a distance x. After it is released, the box slides up a frictionless incline as shown in the figure and eventually stops. If we repeat this experiment but instead compress the spring a distance of 2x
just as it moves free of the spring, the box will be traveling twice as fast as before.