Answer:
C) Turbines
Explanation:
C. because as the water flows, its kinetic energy is used to turn a turbine.
Answer:
C. Burning coal tends to harm the environment more than using solar panels.
Explanation:
When coal is burned, it reacts with the oxygen in the air. This reaction converts the stored potential energy, which turns into thermal energy, which is released as heat. But it also produces methane and carbon dioxide which is released into the air.
Answer:
20 N
Explanation:
By Newton's 2nd law,
The rate of change of momentum is directly proportional to the unbalance force applied on the object,
By that you can get the equation,
F = ma
= 5 × 4 = 20 N
Not sure if this it completely right but here’s what I got: 77.16050617284 J
