When the amplitude of a body executing SHM becomes twice what happens?
1
Maximum potential energy is doubled
2
Maximum kinetic energy is doubled
3
Total energy is doubled
4
Maximum velocity is doubled
Official Solution
Correct Option: (4)
Step 1: Concept
. Step 2: Analysis
If becomes , then becomes , which is twice the original. Step 3: Energy (Optional)
Total energy , so if doubles, energy quadruples. Final Answer: (D)
02
PYQ 2010
medium
physicsID: met-2010
Two pendulums have time periods T and 5T/4. They start SHM at the same time from the mean position. What will be the phase difference between them after the bigger pendulum completed one oscillation?
1
2
3
4
Official Solution
Correct Option: (2)
Step 1: Analysis
The bigger pendulum takes to complete one vibration. Step 2: Comparison
In this time, the smaller pendulum completes vibrations. Step 3: Phase Difference
The lead is seconds, which corresponds to radians or . Final Answer: (B)
03
PYQ 2015
medium
physicsID: met-2015
The two blocks of masses and are kept on a smooth horizontal table as shown. Block of mass but not is fastened to the spring. If now both the blocks are pushed to the left, so that the spring is compressed at a distance . The amplitude of oscillation of block of mass after the system is released, is
1
2
3
4
Official Solution
Correct Option: (1)
Step 1: Understanding the Concept:
Use energy conservation. Spring potential energy converts into kinetic energy of both blocks. After separation, oscillates with its share of energy. Step 2: Detailed Explanation:
Initial potential energy: . At natural length, both blocks have same velocity :
Kinetic energy of :
This becomes maximum potential energy of spring:
Solve for amplitude: . Step 3: Final Answer:
04
PYQ 2019
medium
physicsID: met-2019
A simple pendulum oscillates in a vertical plane. When it passes through the mean position, the tension in the string is 3 times the weight of the pendulum bob. What is the maximum displacement of the pendulum of the string with respect to the vertical?
1
30°
2
45°
3
60°
4
90°
Official Solution
Correct Option: (4)
Step 1: Understanding the Concept:
At mean position, . Step 2: Detailed Explanation:
Using energy:
Step 3: Final Answer:
Maximum displacement is 90°.
