Question

An ideal solenoid of length 10 cm consists of a wire wrapped tightly around a wooden core. The magnetic field strength is 4.0 T inside the solenoid. If the solenoid is stretched to 25 cm by applying a force to it, what does the magnetic field become

Answer 1

The magnetic field will become 1.6 T.

Step-by-step explanation:

Given;

initial length of the solenoid, L₁ = 10 cm

final length of the solenoid, L₂ = 25 cm

Magnetic field inside a solenoid is given by;

`B = (\mu_o NI)/(L) \\\\BL =\mu_oNI = k\\\\BL = k\\\\B_1L_1 = B_2L_2\\\\B_2 = (B_1L_1)/(L_2)\\\\B_2 = (4*10)/(25)\\\\B_2 = 1.6 \ T`

Therefore, the magnetic field will become 1.6 T.