Physics
posted by Anonymous .
A car is stopped at a traffic light. It then travels along a straight road so that its distance from the light is given by x(t) = bt2  ct3, where b = 2.60 m/s2 and c = 0.150 m/s3.
(a) Calculate the average velocity of the car for the time interval t = 0 to t = 8.0 s.
m/s
(b) Calculate the instantaneous velocity of the car at the following times:
i) t = 0
m/s
ii) t = 4.0 s
m/s
iii) t = 8.0 s
m/s
(c) How long after starting from rest is the car again at rest

a) average velocity= (x(8)x(0))/8
b) v(t)=x'(t)=2bt3ct^2
Put t=0;4;8 and calculate. I assume you know calculus to get v(t)=x'(t) 
You can do this yourself.
Please use ^ before exponents.
For average velocity, compute
x at 0 and 8 s and divide by the elapsed time, 8s
For instantaneous velocity, take the derivative dx/dt at each of the times listed. 
a pendulum has a period on the earth of 1.35s.what is its period on the surface of the moon where g=1.62m/s^2