William Gilbert is known as the father of electricity.
He should a step-up transformer with k=220/120=1.83 so output coil must have 240*1.83=440 turns
Answer:
b.only when the current in the first coil changes.
Explanation:
An induced current flow in the second coil only when there is a change in current in the first cool. A steady current will produce no change in flux (due to magnetic effect of a current) by the first coil, and according to Faraday, induced current is only produced when there is a change in flux linkage.
C. is correct : ) it is applied when you push and that causes the desk to move
Answer:
The girl has greater tangential acceleration
Explanation:
The angular acceleration (
) of the merry go round is equal to the rate of the change of the angular velocity,
:

Since all the points of the merry go round complete 1 circle in the same time, the angular velocity of each point of the merry go round is the same, and so all the points also have the same angular acceleration.
The tangential acceleration instead is given by

where
is the angular acceleration
r is the distance from the centre of the merry go round
Since the girl is near the outer edge and the boy is closer to the centre, the value of r for the girl is larger than for the boy, so the girl has greater tangential acceleration.