Answer:
The answer is 100J.
Explanation:
In classical mechanics, kinetic energy (KE) is equal to half of an object's mass (1/2*m) multiplied by the velocity squared. In this question, the mass is equals to 50kg and the velocity is 2m/s
Now,
25kg×4m/s^2 = 100kgm/s^2 or 100J
A big part of the reason that mirrors are seldom if ever used to generate
electricity is the simple fact that there is no way to generate electricity using
mirrors. They are as useless for the purpose as smoke is, although there are
those who have used both items simultaneously to create the impression that
they have succeeded in that attempt.
Since work is the change in kinetic energy, the efficiency of a machine can be stated as the percentage of the output work divided by the input work minus the work lost from to friction and heat. Multiply Eff by 100% to get the efficiency percentage.
It would be option A (a decrease in mass with an increase in volume)