Question

the coefficient of friction between a horizontal surface and a moving body is u with what speed must a body of mass m be projected parallel to the surface to travel a distance s before stopping​

Answer 1

Explanation:

let us consider that block is initially protected with velocity v on rough horizontal surface then it's stop after moving distance s.

we know from work energy theorem that energy of a system can be converted into work.

so kinetic energy will be lost due to friction. so energy of block will be losses into work against friction.

so

kinetic energy =work done by friction force

1/2 mv^2 = {\mu} mgs

v=sqrt{2{\mu} gs}