Kinetic Energy = 1/2xmassx(velocity)^2
Input values;
K.E=1/2x7kgx(4m/s)^2
K.E.=56J
Explanation:
It is given that,
Relativistic Mass of the stone, m₀ = 0.6
Mass, 
Relativistic mass is given by :
.........(1)
Where
c is the speed of light
On rearranging equation (1) we get :



v = 0.61378 c
or
v = 0.6138 c
So, the correct option is (c). Hence, this is the required solution.
Answer:
Amount of work done by Joanne = 80 joule
Explanation:
Given:
Displacement of ball = 2 meters
Force applied = 40 newtons
Find:
Amount of work done by Joanne
Computation;
Work done = Force applied x Displacement
Amount of work done by Joanne = Force applied x Displacement of ball
Amount of work done by Joanne = 40 x 2
Amount of work done by Joanne = 80 joule
20 hours you do 300 divided by 15 and get 20 hours