chill00
Oct 6, 2008, 04:18 PM
A 2000 kg car is slowed down uniformly from 21.0 m/s to 5.00 m/s in 5.40 s.
(a) What average total force acted on the car during that time?
N
(b) How far did the car travel during that time?
M
Credendovidis
Oct 6, 2008, 04:24 PM
Hello chill00
This link will provide you with a good explanation how to approach this question ! (LINK) (http://www.glenbrook.k12.il.us/GBSSCI/PHYS/CLASS/1DKin/U1L1d.html)
Also see chapter acceleration !
Success with your homework !
:)
Unknown008
Oct 7, 2008, 05:13 AM
For the first one, use F=ma. Here, since the car is deccelerating, so, the acceleration will be negative, or you work it out all positive but then you specify the direction of the force. The acceleration is the rate of change in speed per unit time. I guess you can do it now.
The other one, try drawing a graph (velocity - time) to help you understand. The distance is given by the area under that graph. It is a trapezium, so, it should be easy.