A man who is running has half the kinetic energy of a boy of half his mass. The man speeds up by 1 `ms^(-1)` and then has the same kinetic energy as the boy. The original speed of the boy was:

A running man has half the KE that a body of half his mass has. The man speeds up by 1.0ms^(-1) and then has the same energy as the boy. What were the original speeds of the man and the boy?

A running man has the same kinetic energy as that of a boy of half his mass. The man speed up by 2 ms^(-1) and the body changes his speed by x ms^(-1) so that the kinetic energies of the boy and the man are again equal. Then x in ms^(-1) is

If the speed of a vehicle is increased by 1 ms^(-1) , its kinetic energy is doubled , then original speed of the vehicle is