The force on a current-carrying wire is minimum when the current is moving at what angle to the magnetic field?

10 degrees
30 degrees
45 degrees
90 degrees

Option A. 10 degrees

Explanation:

When a charged particle is placed magnetic field, it will possess magnetic force. The force acting on the particle is given by :

i and l are current and length of wire

Here,

is the angle between velocity and magnetic field.

The force is minimum when the value of is minimum.

It is clear that the value of sin(10) is minimum out of all other angles. So, the force on a current-carrying wire is minimum when the current is moving at what angle of 10 degrees to the magnetic field

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s