If a source of sound waves is rapidly approaching a person the sound heard by the person appears to have

Answer

Increasing frequency

Explanation

When the source of sound and the observer are moving towards each other the frequency tends to be increasing. Since wavelength is inversely proportional to the frequency, the wave decreases when the frequency increases.

These effect is called the Doppler effect named after the Austrian physicist Christian Doppler, who described the phenomenon in 1842

unlike poles attract

we need to know the time interval during which the force acts. impulse of force = momentum change