40 N. If you’re using F=MA MxA would be 10x4 which would get you 40 N
Because the coefficient of friction depends on the surface
Consider that the bar magnet has a magnetic field that is acting around it, which will imply that there is a change in the magnetic flux through the loop whenever it moves towards the conducting loop. This could be described as an induction of the electromotive Force in the circuit from Faraday's law.
In turn by Lenz's law, said electromotive force opposes the change in the magnetic flux of the circuit. Therefore, there is a force that opposes the movement of the bar magnet through the conductor loop. Therefore, the bar magnet does not suffer free fall motion.
The bar magnet does not move as a freely falling object.
Answer:
Explanation:
Work done on the lever ( input energy ) = force applied x input distance
= 24 N x 2m = 48 J
Work done by the lever ( output energy ) = load x output distance
= 72 N x 0.5m = 36 J
efficiency = output energy / input energy
= 36 J / 48 J
= 3 / 4 = .75
In percentage terms efficiency = 75 % .
Answer:

Explanation:
First, let's find the voltage through the resistor using ohm's law:

AC power as function of time can be calculated as:
(1)
Where:

Because of the problem doesn't give us additional information, let's assume:

Evaluating the equation (1) in t=3600 (Because 1h equal to 3600s):
