One of the conditions for equilibrium is that the sum of torques must be zero. Suppose that the plank is in equilibrium with some weights on it. The torque about the fulcrum will be zero. Will the torque calculated about the left edge of the plank also be equal to zero

What is relative velocity? in which condition is relative velocity known by adding the velocity of the first body and that of the second body

Alead ball is dropped into a lake from a diving board 5m above the water . it hits the water with a certain velocity and then sink with constant velocity in bottom . it reaches the bottom 5 second after it is dropped if g= 10m/s2 . find depth of the lake and average velocity of the ball ?

Rohit is trying to tune an instrument