The answer is C for this question
I think it is known as a pulsar!
Answer:
0.5 A
Explanation:
N = 20, A = 50 cm^2 = 50 x 10^-4 m^2, dB = 6 - 2 = 4 T, dt = 2 s, R = 0.4 ohm
The induced emf is given by
e = - N dФ/dt
Where, dФ/dt is the rate of change of magnetic flux.
Ф = B A
dФ/dt = A dB/dt
so,
e = 20 x 50 x 10^-4 x 4 / 2 = 0.2 V
negative sign shows the direction of magnetic field.
induced current, i = induced emf / resistance = 0.2 / 0.4 = 0.5 A
Answer:
Linear expansivity is the fractional increase in length of a specimen of a solid, per unit rise in temperature. If a specimen increases in length from l1 to l2 when its temperature is raised θ°, then the expansivity (α) is given by: l2 = l1(1 + αθ). This relationship assumes that α is independent of temperature. This is not, in general, the case and a more accurate relationship is: l2 = l1(1 + aθ + bθ2 + cθ3…), where a, b, and c are constants.
l2 = l1(1 + αθ).
l2 = l1(1 + aθ + bθ2 + cθ3…),