Question

A car travels 30 kilometers north for 2 hours, then travels 45 kilometers east for 3 hours. The car then drives south for 30 kilometers for 1.5 hours, finally travels west for 25 kilometers in 0.5 hours. What is the speed of the car? What is the velocity of the car?

Answer 1

*Let north and east as positive direction.
1. a = +30 km / 2 hr
a = +15 km/hr

2. a = +45 km / 3 hr
a = +15 km/hr

3. a = -30 km / 1.5 hr
a = -20 km/hr

4. a = -25 km / 0.5 hr
a = -50 km/hr

speed = (15+15+20+50) / 4
= 25 km/hr

velocity:
(horizontal): (+15-50)= -35 km/hr
(vertical): (+15-20)= -5km/hr
v = sqrt(35^2 + 5^2)
v = 35.36 km/hr