When you touch a hot object, a reflex controls your movements. but how do you know the object was hot?

If the spring constant k of a pogo stick is 3500 n m and the weight of the person on the pogo stick is 700 n, how much is the spring in the botom of the pogo stick compressed?

An athlete is holding 24 lb of weights at a height of 6 inches above the stack as shown. to lower the weights, she applies a constant force of 5 lb to the handle. determine the velocity of the weights immediately before they hit the stack.

Aball thrown by ginger is moving upward through the air. diagram a shows a box with a downward arrow. diagram b shows a box with an upward arrow. diagram c shows a box with a downward and upward arrow equal in size. diagram d shows a box with a downward and upward arrow with the downward arrow larger in size. which force diagram represents the forces on the ball? you may neglect the effects of air resistance.