1.A body of certain mass is kept at a height of 15m from the ground, taking the value of g as 10m/s find out the mass of the body when it posses the energy of 300J. 2. A boy runs at a velocity of 50m/s. If he has the mass of 50kg what will be the energy possessed by him?

1.#potential energy = PE, m = mass in kg, g = force of gravity, h= vertical height above the ground.  ** means to the power of ie exponent. * means multiply.

PE = mgh

300 = m(10)(15)

m = 300/(10)(15)

m= 2kg

2. KE = 1/2 mv**2

     = 1/2(50)(50)**2

     = 2500 joules

Explanation

Is as in solution

they should be similar or the same

measuring things 1 litre of water