The time taken to complete 10 oscillations by a seconds pendulum is

Options

A. 5sec
B. 10sec
C. 15sec
D. 20sec

Answer

To solve the question about the time taken to complete 10 oscillations by a seconds pendulum, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of a Seconds Pendulum**:
A seconds pendulum is defined as a pendulum that takes exactly 2 seconds to complete one full oscillation (back and forth motion).

2. **Identify the Time Period**:
The time period (T) of a seconds pendulum is 2 seconds. This means that every complete oscillation takes 2 seconds.

3. **Calculate the Time for 10 Oscillations**:
To find the total time taken for 10 oscillations, we multiply the time period of one oscillation by the number of oscillations:
\[ \text{Total Time} = \text{Time Period} \times \text{Number of Oscillations} \]
\[ \text{Total Time} = 2 \, \text{seconds} \times 10 = 20 \, \text{seconds} \]

4. **Conclusion**:
Therefore, the time taken to complete 10 oscillations by a seconds pendulum is 20 seconds.

### Final Answer:
The time taken to complete 10 oscillations by a seconds pendulum is **20 seconds**.

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