Physics Homework#1, T,3

Answer the following questions (show your full work)

  1. Use the diagram given to find the force per unit length between the two wires shown.

 

  1. The distance between two parallel wires carrying currents of 10 A and 20 A is 10 cm. Determine the magnitude and direction of the magnetic force acting on the length of 1 m of wires, if the currents are carried a) in the same direction, b) in the opposite direction.

 

  1. The force per meter between the two wires of a jumper cable being used to start a stalled car is 0.225 N/m. (a) What is the current in the wires, given they are separated by 2.00 cm? (b) Is the force attractive or repulsive?

 

  1. The wire carrying 400 A to the motor of a commuter train feels an attractive force of 4.00 × 10−3 N/m due to a parallel wire carrying 5.00 A to a headlight. (a) How far apart are the wires? (b) Are the currents in the same direction?

 

  1. A 2.50-m segment of wire supplying current to the motor of a submerged submarine carries 1000 A and feels a 4.00-N repulsive force from a parallel wire 5.00 cm away. What is the direction and magnitude of the current in the other wire?