If Sonu is driving a car at a speed of 20 m/s, then in how much time Sonu will cover a distance of 936 km ?

Options

A. 18 hr
B. `46.8` hr
C. 21 hr
D. 13 hr

Answer

To solve the problem of how long it will take Sonu to cover a distance of 936 km while driving at a speed of 20 m/s, we can follow these steps:

### Step 1: Convert the speed from m/s to km/h
The speed is given as 20 m/s. To convert this speed into kilometers per hour (km/h), we use the conversion factor:
1 m/s = 3.6 km/h.

So, we calculate:
\[ \text{Speed in km/h} = 20 \, \text{m/s} \times 3.6 \, \text{(km/h per m/s)} = 72 \, \text{km/h} \]

### Step 2: Use the formula for time
The formula to calculate time when distance and speed are known is:
\[ \text{Time} = \frac{\text{Distance}}{\text{Speed}} \]

### Step 3: Substitute the values into the formula
We know the distance is 936 km and the speed is 72 km/h. Now we can substitute these values into the formula:
\[ \text{Time} = \frac{936 \, \text{km}}{72 \, \text{km/h}} \]

### Step 4: Calculate the time
Now we perform the division:
\[ \text{Time} = 13 \, \text{hours} \]

Thus, it will take Sonu 13 hours to cover the distance of 936 km at a speed of 20 m/s.

### Final Answer:
Sonu will take **13 hours** to cover the distance.

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