B5. (a) A toothed wheel tachometer encoder with 12 teeth is used to measure the speed of the motor. It produces an output of 80 pulses per second. What is the speed of the motor in r.p.m (revolutions per minute) and what is the maximum possible error in the measurement with this system? 400 rpm (6 marks) or
(b) One type of vibration sensor is the Variable Reluctance Proximity Sensor. Explain the working principle of Variable Reluctance Proximity Sensors and list two example applications. (8 marks)