8.2– Applying Magnetic forces-2

The force exerted on a current-carrying wire

located in an external magnetic field is directly

proportional to which of the following?

• Current strength

• Field strength

• Length of the wire

• Thickness of the wire

A current-carrying wire lies between the poles of

two magnets, as shown.

What is the direction of the force on the wire?

• Into the plane of the paper

• Out of the plane of the paper

• Towards the N-pole

• Towards the S-pole

Assume that a 19 cm length of wire is carrying a

current perpendicular to a 4.1 T magnetic field and

experiences a force of 7.6 mN. What is the current in

the wire?

• $3.4×10^{-7\ }𝐴$
  

• $1.0×10^{-7\ }𝐴$

• $9.8\times10^{-3}\ 𝐴$

A current carrying conductor experiences a force when placed in an external magnetic field. What is the formula for calculating this force?

•  $qvB\sin\theta$  

•  $IlB\sin\theta$  

•  $qvB\cos\theta$  

•  $IlB\cos\theta$  

The force on a charged particle created by its

motion in a magnetic field is maximum at what angle

between the particle velocity and field?

• 90

• 0

• 180