Question

The strength of the Earth’s magnetic field B at the equator is approximately equal to 5 × 10−5 T. The force on a charge q moving in a direction perpendicular to a magnetic field is given by F = q v B, where v is the speed of the particle. The direction of the force is given by the right-hand rule. Suppose you rub a balloon in your hair and your head acquires a static charge of 4 × 10−9 C. If you are at the equator and driving west at a speed of 60 m/s, what is the strength of the magnetic force on your head due to the Earth’s magnetic field? Answer in units of N

Answer 1

1.2 x 10⁻¹¹ N

Step-by-step explanation:

B = magnitude of magnetic field at the equator = 5 x 10⁻⁵ T

q = magnitude of charge acquired by the head = 4 x 10⁻⁹ C

v = speed of driving at the equator = 60 m/s

Magnitude of magnetic force on the head at the equator is given as

F = q v B

Inserting the above values in the equation

F = (4 x 10⁻⁹) (60) (5 x 10⁻⁵)

F = 1.2 x 10⁻¹¹ N