Question

Following are few motions which relate to measuring time : 1. motion of pendulum 2. sand falling in an hourglass 3. change in position of shadow Which of these motions can be considered as a periodic motion?Required to answer.

(1 Point)

a. only 1

b only 2

c. both 1 and 2

d. both 2 and 3​

Answer 1

Both 1and 2 is the answer

Answer 2

Answer:

The motions which can be considered as periodic motions are 1) motion of pendulum and 2) sand falling in an hourglass.

So the correct option is option c (both 1 and 2).

Explanation:

Periodic motion:

• When an object moves to and fro from its position of rest, it is known as the periodic motion.
• It is a motion which repeat itself after a regular intervals of time.

1) Motion of pendulum: It is a periodic motion. The bob of the pendulum moves back and forth from its position of rest.

2) Sand falling in an hour glass: Sand bulb is made up of two glass connected by a thin tube between them. Sand from the upper bulb falls into the lower bulb at fixed interval of time

So, this motion is an example of a periodic motion.

3) Change in position of shadow: It is not a periodic motion because shadow does not comes back to its position or moves back and forth after a fixed time.

RESULT: 1) Motion of pendulum and 2) Sand falling in an hour glass both are periodic motion.