A car moving at 108 km/h finds another car in front of it going in the same direction at 72 km/h. The first car sounds a horn that has a dominant frequency of 800 Hz. What will be the apparent frequency heard by the driver in the front car? Speed of sound in air = 330 m/s.

Explanation

To solve the problem, we need to find the apparent frequency heard by the driver in the front car when the first car sounds its horn. We will use the Doppler effect formula for sound.

### Step-by-Step Solution:

1. **Convert Speeds from km/h to m/s**:
- The speed of the first car (source) is given as 108 km/h.
- To convert km/h to m/s, we use the conversion factor: \(1 \text{ km/h} = \frac{1}{3.6} \text{ m/s}\).
- Therefore, the speed of the source car \(V_s\) is:
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