Quiz3week1

• Accompany your solution with an explanation of the meaning of each step and with a flow diagram.

• Then solve the same problem using the equations of uniformly accelerated motion.

• Make up a problem for situation # 8, and solve it using the equations of uniformly accelerated motion.

A= 8cm/s^2 , v0 = 6cm/s, ‘dt = 9s

Vf = (8cm/s^2)*9s +6cm/s = 72cm/s + 6cm/s = 78cm/s

‘ds = ((v0 +vf)/2) *’dt = 42cm/s *9s = 378cm

By multiplying acceleration by change in time and subtracting initial velocity we can determine final velocity.

By adding the initial velocity to the final velocity and dividing by 2 we can determine the average velocity. By multiplying the average velocity by the change in time we can determine displacement.

8cm/s^2 * 9s =72cm/s = ‘dv

6cm/s + 72cm/s = 78cm/s = vf

(78cm/s + 6cm/s)/2 = 42cm/s= vAve

42cm/s * 9s = 378cm = ‘ds

Vf = 25cm/s, a = 5cm/s^2, ds = 45cm

vf^2 = v0^2 + 2 a `ds.

(25cm)^2 = v0^2 + 2(5cm/s^2) *45cm

625cm^2/s^2 = v0^2 + 450cm^2/s^2

25cm/s – 21cm/s =v0 = 4cm/s

(21cm/s)/ (5cm/s^2) = 4.2s = ‘dt

It took me a minute to figure out where your first problem ended and second began. Actuallly more like 10 seconds, so no problem. But it's a good idea to include a little labeling.

Your solutions are very good. You're in good shape at this point.