A spring has a spring constant k = 20N/cm. What load is needed to produce an extension of 2.5cm?

The crank oa rotates in the vertical plane with a constant clockwise angular velocity ω0 of 5.6 rad/s. for the position where oa is horizontal, calculate the force under the light roller b of the 10.6-kg slender bar ab.

Suppose you increase your walking speed from 7 m/s to 13 m/s in a period of 2 s. what is your acceleration?

Ahockey puck sliding along frictionless ice with speed v to the right collides with a horizontal spring and compresses it by 3.0 cm before coming to a momentary stop.