Physics Advanced Level Paper 2 June 2001 Question 3 Current Electricity

Physics Advanced Level Paper 2 June 2001 Question 3   Current Electricity

A car is normally threaded with wire loops. Donlop tyres have about 200 loops a tyre. A car running on such tyres travels at speed of 16.7 ms-1 along a level road such that the magnetic field of the earth makes an angle of 530 with the axis of the tyre at all the times. If the magnetic field is 1.2 x 10-5 T, calculate 

i. The induced current through a loop if the tyre’s diameter is 0.65 m and the resistance per unit length is 8.0 x 10-3 ohms per meter. 

ii. How much power is generated on the tyre due to the motion in the earth’s magnetic field? 

iii. What does it suggest to you about the usage of threaded tyres?