Which of the two requires an electric cell for its working : a quartz clock or a pendulum clock ?

Answer

To determine which of the two clocks requires an electric cell for its working, we can analyze the functioning of both the quartz clock and the pendulum clock.

### Step-by-Step Solution:

1. **Understand the Functioning of a Pendulum Clock**:
- A pendulum clock operates based on the principle of simple harmonic motion.
- It uses the swinging motion of a pendulum to keep time.
- The pendulum swings back and forth at a regular interval, which is used to measure time.
- Since it relies on mechanical movement and not on electrical components, it does not require an electric cell for its operation.

2. **Understand the Functioning of a Quartz Clock**:
- A quartz clock uses a quartz crystal to keep time.
- The quartz crystal vibrates at a specific frequency when an electric current passes through it.
- This vibration is very stable and accurate, making quartz clocks precise timekeepers.
- To generate the electric current needed for the quartz crystal to vibrate, a quartz clock requires an electric cell (battery).

3. **Conclusion**:
- Based on the analysis, the pendulum clock does not require an electric cell, while the quartz clock does.
- Therefore, the answer to the question is that the quartz clock requires an electric cell for its working.

### Final Answer:
The quartz clock requires an electric cell for its working, while the pendulum clock does not.

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