# Physics Numerical for class 9 motion & other chapters with answers & [PDF]

Last updated on December 12th, 2023 at 01:53 pm

**Numericals based on simple Pendulum motion**

61) Two simple pendulums *A *and *B *have equal lengths, but their bobs weigh 50 gf and l00 gf respectively. What would be the ratio of their time periods? Give a reason for your answer.

**Solution: solution Q61 **

62) Two simple pendulums *A *and *B *have lengths of 1·0m and 4·0 m respectively at a certain place. Which pendulum will make more oscillations in 1 minute? Explain your answer.

**Solution: solution Q62**

63)A simple pendulum completes 40 oscillations in one minute. Find its (a) frequency, (b) time period.

**Solution: solution Q6**3

64) The time period of a simple pendulum is 2 s. What is its frequency? What name is given to such a pendulum?

**Solution: solution Q6**4

65) A seconds’ pendulum is taken to a place where the acceleration due to gravity falls to one-fourth. How is the time period of the pendulum affected, if at all? Give reason. What will be its new time-period?

**Solution: solution Q6**5

66) Find the length of a seconds’ pendulum at a place where *g *= 10 m/s^{2} (Take ∏= 3·14).

**Solution: solution Q6**6

67) A pendulum completes 2 oscillations in 5 s. (a) What is its time period? (b) If *g *= 9·8 m /S^2, find its length.

**Solution: solution Q6**7

68) Compare the time periods of two pendulums of length 1 m and 9 m

**Solution: solution Q6**8

69) The time periods of two simple pendulums at a place are in a ratio of 2:1. What will be the ratio of their length?

**Solution:** **solution Q6**9

70) It takes 0·2 s for a pendulum bob to move from the mean position to one end. What is the time period of the pendulum?

**Solution: solution Q70**

71) How much time does the bob of a seconds’ pendulum take to move from one extreme of its oscillation to the other extreme?

**Solution: solution Q**71

I find this collection of physics problems very useful. Our class teacher has also prescribed us to solve these problems. Thank you.

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Thanks for your comments and suggestion, Shilpa. We will certainly plan for it.

Hi Ayan, Good to know this. Best wishes.

Thanks Dip for your inspiring words.