Answer:
D I think I might be wrong its been a while scense I did something like that
Answer:
True
Explanation:
I am not 100% on the answer for this question but i hope it was right
-30 I think sorry if I’m wrong
Answer:
The rate of change of magnetic field is 2.23 T/s.
Explanation:
Given that,
Dimension of rectangular coil is 7.2 cm by 3.7 cm.
Number of turns in the coil, N = 104
Resistance of the coil, R = 12.4 ohms
Current, I = 0.05 A
We need to find the rate of change of magnetic field in the coil. The induced emf is given by the rate of change of magnetic flux. So,

Ohm's law is :

So,

So, the rate of change of magnetic field is 2.23 T/s.
Answer:
r = 1.61 x 10^{11} m
Explanation:
energy radiated (H) = 2.7 x 10^31 W
surface temperature (T) = 11,000 k
assuming ε = 1 and taking σ = 5.67 x 10^{-8} W/m^{2}.K^{4}
we can find the radius of the star from the equation below
H = A x ε x σ x T^{4}
where area (A) = 4 x π x r^{2} (assuming it is a sphere)
therefore the equation becomes
H = 4 x π x r^{2} x ε x σ x T^{4}
2.7 x 10^31 = 4 x π x r^{2} x 1 x 5.67 x 10^{-8} x (11,000)^{4}
r = 
r = 1.61 x 10^{11} m