Astone is dropped in a river from a bridge. if it takes 4 seconds to reach surface of water ,calculate the depth of the water level from the bridge .also calculate the velocity with which the stone strikes on the water surface

When applying kirchhoff's rules, one of the essential steps is to mark each resistor with plus and minus signs to label how the electric potential changes from one end of the resistor to the other. the circuit in the drawing contains four resistors, each marked with the associated plus and minus signs. however, one resistor is marked incorrectly. which one is it?

A14 kg rock starting from rest free falls through a distance of 5.0 m with no air resistance. find the momentum change of the rock caused by its fall and the resulting change in the magnitude of earths velocity. earth mass is 6.0 * 10^24 kg. show your work assuming the rock earth system is closed.

Agirl throws a ball. if the ball's acceleration is 12 m/sec/sec and its mass is 0.5 kg, how much force did the girl apply to the ball?