An open knife of mass m is dropped from a height h on a wooden floor. If the blade penetrates up to the depth d into the wood. The average resistance offered by the wood to the knife edge is .

An open knife edge of mass M is dropped from a height 'h' on a wooden floor if the blade penetrates a distance 'S' into the wood average resistance offered by the wood to the blade is:

An open knife edge of mass 200g is dropped from height 5m on a cardboar. If the knife edge penetrates a distance 2 m into the cardboard. Find the average resistance offered by the cardboar to the knife edge (in N). (g = 10 m//s^(2))

A particle of mass m is dropped from a great height h above the hole in the earth dug along its diameter.

An iron nail is dropped from a height h on the level of a sand bed. If it penetrates through a distance x in the sand before coming to rest, the average force exerted by the sand on the nail is

A block of mass m is dropped from height h above the ground. Find out the speed of the block when it reaches the ground.

Hammer of mass M strikes a nail of mass 'm' with a velocity 20 m/s into a fixed wall. The nail penetrates into the wall to a depth of 1 cm. The average resistance of the wall to the penetration of the nail is

A ball is dropped from a height of 5 m onto a sandy floor and penetrates the sand up to 1 m before coming to rest. The retardation of the ball in sand (assuming it to be uniform) will be