Natural sources of light include our sun and other stars, where the source of energy is nuclear energy (recall that the moon does not produce light but merely reflects sunlight), lightning, where the source is electrical, and fire, where the energy source is chemical.
Answer:
80.6 mV
Explanation:
Parameters given:
Number of turns, N = 115
Radius of coil, r = 2.71 cm = 0.0271m
Time taken, t = 0.133s
Initial magnetic field, Bin = 50.1 mT = 0.0501 T
Final magnetic field, Bfin = 90.5 mT = 0.0905 T
Induces EMF is given as:
EMF = [(Bfin - Bin) * N * A] / t
EMF = [(0.0905 - 0.0501) * 115 * pi * 0.0271²] / 0.133
EMF = (0.0404 * 115 * 3.142 * 0.0007344) / 0.133
EMF = 0.0806 V = 80.6 mV
Answer:
0.002833 sec
Explanation:
Speed of light in vacuum is 
Given distance = 850 km = 850×1000=850000 m
We have to calculate the time that light take to travel the distance 850 km
Time 
So the time taken by light to travel 850 km is 0.002833 sec
If its just a number 2,300 is an answer