The correct answer is A.
A power station works on the principle of boiling water to create steam, which turns a turbine, generating a potential difference in a transformer with the magnets. The transformer is connected to a circuit, which hence induces a current, generating power.
False the strength off the magnet lessens the farther you get from it
The conservation of momentum states that the total momentum in a system is constant if there is no external force acting on the system. The total momentum in the gun bullet system is 0 so it must stay that way.
The momentum of the bullet is mv = 0.015*500=7.5
The momentum of the gun must be the same to keep the total momentum of the system equal to zero, so we know that p = 7.5 for the gun.
Substituting this in we get:
7.5=3.1x
x=7.5/3.1
x=2.42
So the speed of the gun is 2.4m/s.
D, it is considered unethical today