P=IV
V=IR
P=I(IR)
P=I²R
375=5²R
R=375/25
R=15
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.
Answer:
a.18.5 m/s
b.1.98 s
Explanation:
We are given that

a.Let
be the initial velocity of the ball.
Distance,x=30 m
Height,h=1.8 m





Substitute the values





Initial velocity of the ball=18.5 m/s
b.Substitute the value then we get

t=1.98 s
Hence, the time for the ball to reach the target=1.98 s