1. Check for Understanding 1
An object accelerates uniformly. It moves from rest and travels a distance of 4 m in one second. Where is the object located after two seconds?
8m b) 16 m c) 32 m
d) 64 m
x=vit+1/2at2
4=0(1)+1/2a(1)2
a=8m/s2
x=vit+1/2at2 x=0(2)+1/2(8)(2)2 x= 16 m

2. Check for Understanding 2
A marathon runner accelerates uniformly from a velocity of 3 m/s to 6 m/s over a distance of 20 m. How long did it take for her to run the 20 m?
Vf2=vi2+2ax
62=32+2a(20)
27=40a
a=0.675 m/s2
x=vit+1/2at2 20=0(t)+1/2(0.675)t2 t=7.7s

3. Check for Understanding
The following equations give the velocity v(t) of a particle in four situations:
v=3
V=4t2 + 2t
V=3t-4
V=5t2-3
To which of these situations do the equations of kinematics apply? A and C
Find the derivatives a=dv/dt and see which acceleration functions are constant

5. The UAM Chase Problem
James Bond is racing Forest Gump. After the race begins, it takes Forrest 3 s to remove his metal braces before he starts running. If Gump accelerates with a constant 3 m/s2 once he begins to run and Bond accelerates with a constant 1.5 m/s2 , what will be the difference in their speeds when Forrest passes Bond?