Which of the following cannot be used for the measurement of time? (a) A leaking tap. (b) Simple pendulum. (c) Shadow of an object during the day. (d) Blinking of eyes.

Soln:

The answer is (d) Blinking of eyes.

Explanation:

Blinking of the eye is not a periodic phenomenon. Eyes do not blink at a fixed interval of time. Hence Blinking of eyes cannot be used for measurement of time.