Question

A person travels in a car from p to q with uniform speed u and returns to p with uniform speed v. The average speed for his round trip is

• A. \(\dfrac{u+v}{2}\)
• B. \(\dfrac{uv}{u+v}\)
• C. \(\dfrac{\sqrt{uv}}{u+v}\)
• D. \(\dfrac{2uv}{u+v}\)
• E. \(\dfrac{uv}{u+v}\)

Hint:

For round trip calculations, remember to use the harmonic mean formula for average speed when the speeds are different in both directions.

Answer 1

The Correct Option is D

Step 1: The average speed for a round trip is given by the formula: \[ {Average speed} = \dfrac{2uv}{u + v} \] Step 2: Option (D) correctly applies this formula, which gives the average speed for the round trip.