A simple pendulum makes 100 oscillation in 25 s. What is the frequency of the pendulum correctto the significant figures?

Explanation

To find the frequency of a simple pendulum that makes 100 oscillations in 25 seconds, we can follow these steps:

### Step 1: Understand the Definition of Frequency
Frequency (f) is defined as the number of oscillations (N) per unit time (T). The formula for frequency is:
\[ f = \frac{N}{T} \]

### Step 2: Identify the Given Values
From the question, we have:
- Number of oscillations (N) = 100
- Time (T) = 25 seconds

### Step 3: Substitute the Values into the Formula
Now, we substitute the values of N and T into the frequency formula:
\[ f = \frac{100 \text{ oscillations}}{25 \text{ seconds}} \]

### Step 4: Perform the Calculation
Calculating the above expression:
\[ f = \frac{100}{25} = 4 \text{ oscillations per second} \]

### Step 5: Convert to Hertz
Since 1 oscillation per second is defined as 1 Hertz (Hz), we can express the frequency as:
\[ f = 4 \text{ Hz} \]

### Step 6: Consider Significant Figures
In the given data, the time (25 seconds) has two significant figures. Therefore, we should express our final answer with the same number of significant figures. Thus, we write:
\[ f = 4.0 \text{ Hz} \]

### Final Answer
The frequency of the pendulum, correct to the significant figures, is:
\[ \boxed{4.0 \text{ Hz}} \]

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