Which of the facts listed below will increase the magnetic field strength of an electromagnet generated from a solenoid? I. Increasing the number of loops. II. Replacing the battery with a new battery of the same voltage. III. Using a bigger iron nail for the core. IV. Increasing the strength of the current flowing through the solenoid. V. Decreasing the strength of the current flowing through the soloenoid. A. I, II, and V B. I, III, and IV C. I, II, and III D. I, II, and IV

B. I, III and IV

Explanation:

The strength of the magnetic field generated by a solenoid is given by the following formula:

B = μ₀NI/L

where,

B = Magnetic Field

μ₀ = Permeability of Free Space

N = No. of Coils

I = Current Magnitude

L = Length of Coil

Strength is also directly proportional to size of the core.

So, to increase the magnetic field strength we can:

1- The number of Loops

2- Increase the amount of Current (for same length)

3- Decrease the length (for same number of loops)

4- Increase Size of Core

So, the correct answer is:

B. I, III and IV

correct it is c.) b b

i think the answer would be reserve.