Serena and Johan had 45 diamond stones. They sold 5 stones .The product of the remaining stones is 124. Find the number of stones each had.

A stone is thrown up with a speed of 9.8ms^-1 . Find the time taken to reach the maximum height.

A stone of mass m is to be thrown to a height h. Find the velocity at that height when PE and KE are equal.

Weighing a stone of lower mass and another of higher mass by using a spring balance. [Mass of a body is the amount of matter contained in it] On the basis of these observations, find out the factor that influences the force of attraction from the earth.