Monday, November 5, 2018

9702/May Jun/12/2015/Q3

An analogue ammeter has a pointer which moves over a scale. Following prolonged use, the
pointer does not return fully to zero when the current is turned off and the meter has become less sensitive at higher currents than it is at lower currents.

Which diagram best represents the calibration graph needed to obtain an accurate current
reading?


Solution:
Answer: C.

The scale reading will not start from "0" since the pointer does not return fully to zero when the current is turned off. So choice "A" and "B" are not the answer.

For choice D, the curve line of the graph shows the higher current get higher scale reading. Which means the higher current is more sensitive than lower current.

Only choice C shows the correct reading and fulfill the conditions of the question mentioned.

Reference: PYQ - May/Jun 2015 Paper 12 Q3

1 comment:

  1. if the scale reading is more that means that sensitivity gets higher too?

    ReplyDelete