The diagram shows two complete pulses on the screen of a cathode-ray oscilloscope. A grid of 1 cm squares covers the screen.

Question 18

The diagram shows two complete pulses on the screen of a cathode-ray oscilloscope. A grid of 1 cm squares covers the screen. The time-base setting is 1 μs cm^-1.

How long does each pulse last?

A 2 μs              B 3 μs              C 4 μs              D 6 μs

Reference: Past Exam Paper – June 2012 Paper 12 Q6

Solution:

Answer: A.

Horizontally, the divisions gives the time while vertically, the division represents the voltage.

Each pulse occupies 2 cm horizontally.

Time-base setting = 1 μs cm^-1

Duration of pulse = 2 × 1 = 2 μs