Question

mass 40g kinetic energy 200 J what is speed

Answer 1

Mass of object= 40g = 0.04 kg

K.E. = 1/2mv^2 = 200 J

       = 1/2 * 0.04 * v * v = 200 J

       = 0.02 * v * v = 200

       = v^2 = 200/0.02

       = v^2 = 1

       = v = 1

So, the speed is 1 m/s

Hope this helps

Answer 2

K.I = mv^2  200= 40 × v^2 V^2= 5 V = √5