Question

1. a person walks 3 kilometers in an hour, rests for an hour, and then walks 3 more kilometers in another hour. What is the average speed of the person over the three hours?

2. a car travels north for 20 km. The car then travels south for 35 km. If north is taken as the positive direction, what is the displacement of the car?

Answer 1

Hey there!

1. To find the average speed of something, you use the formula d=rt, or distance equals rate (speed) multiplied by time. We can plug what we have into this equation to find the average speed. The distance is 6 km, and the time is three hours.

6=3r

Now we sole

r=2

Therefore, the average speed is 2 km per hour.

2. If we were to put this on a vertical number line, the car would be at -15. Displacement is the change in original position. If it was originally at point 0, it's displacement is 15 km south. Because it says that north is a positive direction, that must mean the south is negative.

Therefore, your answer is -15.

I hope this helps! Have a great day!

Answer 2

Answer:

1. 2km/h   2. -15km

Explanation:

1. speed=whole distance/time=(3+0+3)/3=2

2. 20-35=-15