Posted by **Helpme** on Wednesday, June 20, 2012 at 4:31am.

A car travels 12 km West, 18 km South. What is the total car displacement? The car takes 10 minutes to travel from each initial position to final position. What is the average speed and velocity?

- Physics -
**drwls**, Wednesday, June 20, 2012 at 5:45am
Since the two trip segments are perpendicular, total displacement is sqrt[12^2 + 18^2] = 21.63 km

Divide than by 1/3 hour for the average velocity, 64.9 km/h. The velocity direction is 56.3 degrees south of west (arctan 1.5)

The average speed is the distance travelled (in any direction) divided by 1/3 hour, or 30 km/(1/3) = 90 km/h

- Physics -
**Helpme**, Wednesday, June 20, 2012 at 5:54am
Could you pleas explain it further? Thanks ;)

- Physics -
**drwls**, Wednesday, June 20, 2012 at 5:57am
What don't you understand?

- Physics -
**Helpme**, Wednesday, June 20, 2012 at 5:57am
what will i divide by 1/3? And why should I divide it by 1/3?

- Physics -
**Helpme**, Wednesday, June 20, 2012 at 5:59am
And where did you get 64.9? Is that the velocity or what?

- Physics -
**drwls**, Wednesday, June 20, 2012 at 10:24am
Divide the displacement (21.63 km) by 1/3 hour, to get the velocity. 1/3 hour is the twenty minutes elapsed time. You presumably want the velocity in km/h, so time must be in hours, not minutes.

The result of the division to get average velocity will be 64.9 km/h, as indicated.

Average velocity is displacement diovided by the time interval.

## Answer This Question

## Related Questions

- More Physics - The diagram below indicates three positions to which a woman ...
- physics - 1. A car travels from one point to another point that is 4km to the ...
- physAH! - A car that is initially at rest moves along a circular path with a ...
- Physics - A car travels in a flat circle of radius R. At a certain instant the ...
- Physics - If a car travels 60 mi. north for one-half hour, 100 mi. west for one ...
- physics - Velocity and displacement with uniform acceleration: 1. A car with an ...
- Physics - a car travels 59.78 miles east in 89.67 minutes, then 89.67 miles ...
- physics - A 1000 kg car in neutral gear slow from 15 m/s to a stop in 5.0 s due ...
- Physics - Two cars travel at the same constant speed. The first car travels for ...
- physics - 1) What average power is required for a runner with a mass of 85 kg to...

More Related Questions