Question

A car moves at 55 km/h for 1.0 h. For the next 0.50 h the car moves at 84 km/h. Calculate the average speed for the entire trip. Show all workings

Answer 1

Answer:

Distance covered by the car in 1.0 h travelling at the speed of 55 km/h is given as,

$d 1= vt \\ = 55 \times 1 \\ = 55 \: km$

Distance covered by the car in 0.5 h travelling at the speed of 84 km/h is given as,

$d2 = vt \\ = 84 \times 0.5 \\ = 42 \: km$

Therefore total distance covered is,

$d = d1 + d2 \\ = 55 + 42 \\ = 97 \: km$

Total time taken is given as,

$t = 1 + 0.5 \\ = 1.5 \: h$

The average speed is given as,

$s = \frac{total \: distamv \: covered}{total \: time \: taken} \\ = \frac{97}{1.5} \\ = 64.67 \: km {h}^{ - 1}$

therefore, the average speed of car during journey is 64.67 km/h