1. 1D Motion Review
Motion Graphs
Use the displacement-time graphs below to answer questions 1-5 not all graphs may be
used while some may be used more than once. These questions are worth 1 point each.
a
b c d e
_____1. Which graph shows an object traveling with a constant positive velocity?
_____2. Which graph shows an object traveling with constant negative acceleration?
_____3. Which graph shows an object traveling with an increasing velocity?
_____4. Which graph shows an object traveling towards the reference point with no
acceleration?
_____5. Which graph shows an object at rest?
Convert the following measurements into the indicated units.
1) 530 mm to km. __________________________
2) 2 pg to cg ________________________
3) 7.1 x 1012 m to km ______________________
3
4) 6.5 x 10 pm to km ______________________
5) 50 m/s to km/hr _______________________
6) 36 km/hr to m/s ______________________
1D Motion Problems
Equations:
a = vf – vI df = vit + ½ at2 df = ½ (vf + vi)t
t
v=d vf2 = vi2 + 2ad
t
1) A car traveling at a constant speed of 30 m/s (~ 67 mi/h) passes a trooper hidden
behind a billboard. One second after the speeding car passes the billboard, the trooper
sets off in chase with a constant acceleration of 3.00 m/ss. How long does it take for
the trooper to overtake the speeding car?
2) A tennis ball with a speed of 10.0 m/s is thrown perpendicularly at a wall. After
striking the wall, the ball rebounds in the opposite direction with a speed of 8.0 m/s.
If the ball is contact with the wall for 0.012 s, what is the average acceleration of the
ball while it is in contact with the wall?
2. 3) A racing car reaches a speed of 40 m/s. At this instant it begins a uniform negative
acceleration, using a parachute and a braking system, and comes to rest 5.0 s later. a)
Determine the acceleration of the car. b) How far does the car travel after the
acceleration starts?
4) A jet airplane lands with a velocity of +100 m/s and can accelerate with a maximum
rate of –5.0m/s2 as it comes to rest. a) From the instant it touches the runway, what
is the minimum time needed before it can come to rest? b) Can this plane land on a
small island airport where the runway is 0.80 km long?
5) A truck on a straight road starts from rest accelerating at 2.0 m/s2 until it reaches a
speed of 20 m/s. Then the truck travels for 20 s at constant speed until the brakes are
applied, stopping the truck in a uniform manner in an additional 5.0 s. a) How long is
the truck in motion? b) What is the average velocity of the truck for the motion
described?
6) A small mailbag is released from a helicopter that is descending steadily at 1.50 m/s.
After 2.00 seconds a) what is the velocity of the mailbag, and b) how far is it below
the helicopter? c) What are your answers to part a & b if the helicopter is rising
steadily at 1.50 m/s?
7) A car starts from rest and travels for 5.0 s with uniform acceleration of +1.5 m/s2. The
driver then applies the brakes causing a uniform acceleration of –2.0 m/s2. If the
brakes are applied for 3.0 s, how fast is the car going at the end of the braking period,
and how far has it gone?