Question four bulbs A,B,C and D are connected in a circuit shown in the figure below, the letters X, Y and Z represent three switches. Which switch is used to operate switch A separately?
Answer: x
Answer:
Inductance as calculated is 13.12 mH
Solution:
As per the question:
Length of the coil, l = 12 cm = 0.12 m
Diameter, d = 1.7 cm = 0.017 m
No. of turns, N = 235
Now,
Area of cross-section of the wire, A = 
We know that the inductance of the coil is given by the formula:

Frequency = 1/time period = 1/0.05 = 20s^-1.
Answer:
6.49 x 10^-8 N
Explanation:
formula is
F= G * ((m1 * m2)/r^2)
F = 6.67x10^-11 * ((6.8*6.8/.218)
F = 6.49 x 10^-8 Newtons