Q 14.1: Find the value of the magnetic field that will cause a maximum force of 7 * 10(-3) N on a 20cm straight wire carrying current of 10 A.

Q 14.2: How fast must a proton move in a magnetic field 2.5 * 10(-3) T such that the magnetic force is equal to its weight?

Q 14.3: A velocity selector has a magnetic field of 0.3T. If a perpendicular electric field of 10000V/m is applied, what will be the speed pf the particle that will pass through the selector?

Q 14.4: A coil of 0.1m * 0.1m and of 200 turns carrying a current of 1 mA is placed in a uniform magnetic field of 0.1T. Calculate the maximum torque that acts on the coil.

Q 14.5: A power line 10m high carries a current 200A. Find the magnetic field of the wire at the ground.

Q 14.6: You are asked to design a solenoid that will give a magnetic field of 0.1 T, yet the current must not exceed 10 A. Find the number of turns per unit length that the solenoid should have.

Q 14.7 What current should pass through a solenoid that is 0.5m long with 10000 turns of copper wire so that it will have a magnetic field of 0.4T.

Q 14.8 A galvanometer having an internal resistance Rg = 15 ohm gives full scale deflection with current Ig = 10 mA. It is to be converted into an ammeter of range 10 A. Find the value of shunt resistance Rs?

Q 14.9 The resistance of galvanometer is 50 ohm and reads full-scale deflection with a current of 2mA. Shown by a diagram on book how to convert this galvanometer into a voltmeter reading 200V full scale.

Q 14.10 The resistance of galvanometer coil is 10 ohm and reads full scale with a current of 1 mA. What should be the values of resistance R1, R2, and R3 to convert this galvanometer into a multi-range ammeter of 100, 10, and 1A as shown in the Fig. P.14.10.