Level Physics
1.
Kinematics Test Review
Describe the motion of each line in the graph below.
A.
Constant, Positive Velocity (moving forward)
B.
Positive velocity w/ negative acceleration (slowing down), then (after crossing
the X-axis) it becomes negative velocity w/ negative acceleration (speeding up).
C.
Negative velocity w/ positive acceleration (slowing down), then (after crossing
the X-axis) it becomes positive velocity w/ positive acceleration (speeding up).
D. _____Negative velocity with negative acceleration (speeding up), then constant
negative velocity (moving in negative direction).
E.
2.
constant negative velocity (moving in negative direction)
A car’s velocity increases uniformly from 3.5 m/s to 82.0 m/s while covering 150.0 m in a
straight line. Find the acceleration and final velocity of the car.
vf2 = vi2 + 2a∆x
822 = 3.52 + 2a(150)
a = 22.37 m/s2
3. If a person walks 5 m west and 7 m north, what is the general direction of their displacement?
North West
4. A ball is thrown to a height of 2.37 m. What speed was the ball thrown with?
∆y = viyt + ½ g∆t2
-2.37 = 0(t) + 1/2 (-9.8) (t2)
t = .7s
vf = vi + a(Δt)
0 = vi + (-9.8)(.7)
vi = 6.86 m/s
5. If a jet on a runway accelerates to a speed of 220 m/s in 2.2 s, what is it’s displacement.
∆x = ½(vi + vf) ∆t
X = ½ (0 + 220) 2.2
x = 242 m
6. An apple falls from a tree and hits the ground with a speed of 25.0 m/s. How long did it take to
fall?
vf = vi + g(Δt)
-25 = 0 + (-9.8) t
t = 2.55 s
7. An engineer is designing the runway for an airport. Of the planes that will use the airport, the
lowest acceleration rate is likely to be 4.0 m/s/s. The takeoff speed for this plane will be 45 m/s
(assuming this minimum acceleration), what is the minimum allowed length for the runway?
vf2 = vi2 + 2a∆x
452 = 02 + 2(4.0)x
x = 253.13 m
8. An object is dropped from rest from the top of a cliff. How long until the speed of the object is
9.81 meters per second?
If dropped, then vi = 0m/s and g = -9.8 m/s2 it would reach a speed of 9.8m/s in 1 sec.
vf = vi + g(Δt)
-9.8 = 0 + (-9.8)(t)
t = 1 sec
9. An astronaut drops a hammer from 3.0 meters above the surface of the Jupiter. If the
acceleration due to gravity on the moon is 27.62 m/s/s, how long will it take for the hammer to
fall to the surface?
vf2 = vi2 + 2g∆y
vf2 = 0 + 2(-27.62)(-3)
vf2 = 12.87 m/s
vf = vi + g(Δt)
-12.87 = 0 + (-27.62)t
t = .47 sec.
10. A dog initially running at a speed of 6.0 meters per second accelerates uniformly to a speed of
12.0 meters per second over a distance of 36 meters. What is the magnitude of his acceleration?
vf2 = vi2 + 2a∆x
12 = 6 + 2a(36)
a = .083 m/s2
11. Indicate the speed & acceleration of the ball at each 1 second interval in the picture below. The
ball is thrown upward with an initial velocity of 30 m/s. For simplicity sake, use g = -10m/s/s.
Time
t=0s
t=1s
t=2s
t=3s
t=4s
t=5s
t=6s
t=7s
t=8s
Veloctity
v = 30 m/s
v = 20 m/s
v = 10 m/s
v = 0 m/s
v =-10 m/s
v = -20 m/s
v = -30 m/s
v = -40 m/s
v = -50 m/s
Acceleration
g = -9.8 m/s2
g = -9.8 m/s2
g = -9.8 m/s2
g = -9.8 m/s2
g = -9.8 m/s2
g = -9.8 m/s2
g = -9.8 m/s2
g = -9.8 m/s2
g = -9.8 m/s2