2015 Physics Study Guide
The mid-term examination will cover chapters 1-6 of the Holt Physics textbook.
Below are practice problems that you should be able to complete.
1.
On the highway at speed 55 mi/h (88.5 km/h), you close your eyes for
half a second during a sneeze. How far do you travel while your eyes
are closed?
2.
A car accelerates from rest to a speed of 112 m/s over a distance of
398 m. Determine the acceleration (assume uniform) of the car.
3.
A brick fall from the top of a building 680 m tall; what is the brick’s
velocity at a point 130 m above the ground?
4.
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 3 m/s 2.
The takeoff speed for this plane will be 65 m/s. Assuming this minimum
acceleration, what is the minimum allowed length for the runway?
5.
A projectile is shot straight up to a height of 180 m. If the projectile’s
initial speed was 3.00 km how long did it take the projectile to reach
s
this height?
6.
7.
A goose leaves a pond and flies 95.0 miles south then flies 40.0 west
and lands in another pond, what is goose’s resultant displacement?
What is the goose’s total distance flown?
A soccer ball is kicked off the ground with an initial velocity of 37.5 m/s
at an angle of 30.0° to the ground.
What is the balls initial horizontal velocity?
What is the balls initial vertical velocity?
How much time will it take for the ball to reach its maximum height?
What is the ball’s maximum height?
8.
A projectile is fired horizontally at a velocity of 45.5 m/s from the top of
cliff 1.00 x102 m high.
How long will it take the projectile to hit the ground ?
How far from the cliff will it strike the ground?
With what velocity will it strike the ground? (note velocity is a vector
therefore speed and direction must be given)
9.
A car traveling at 22.4 m/s skids to a stop in 2.55 s. Determine the
skidding distance of the car (assume uniform acceleration).
10.
A net force of 15 N is exerted on an object to cause it to accelerate at a
rate of 5 m/s2. Determine the mass of the object.
11.
A rocket is launched straight up from the ground with an initial velocity
of 75 m/s.
a) How long does it take to reach its maximum height?
b) What is its maximum height?
c) What is its total time in the air?
d) What is its velocity upon impact with the ground?
e) The rockets total displacement?
12. Suppose the above rocket is launched at 45° to the ground.
a) How long does it take to reach its maximum height?
b) What is its maximum height?
c) What is its range (x displacement)?
13. A 200 kg barge is being towed across a lake by two boats. One boat is
exerting a force of 500 N to the south and the second boat is exerting a
force of 1200 N to the west.
a) What is the combined force?
b) What is the resulting acceleration?
c) What is the barge’s direction?
14. What force is needed to accelerate a 200.0 kg box across the ground at
3.00 m/s2 if the coefficient of friction between the box and ground is
0.265?
15. A 10.0 kg object is dragged across the floor at constant velocity by a
50.0 N applied force at 35.0 above the horizontal. What is the
coefficient of friction?
16. A train with a mass of 1.8´10 5 kg is moving at 15 m/s when the engineer
applies the brakes. If the braking force is constant at 3.5´10 4 N
a) how long does it take the train to stop?
b) How far does the train travel during this time?
USEFUL EQUATIONS
Dx =
v f + vi
Dt
2
1
Dx = vi Dt + aDt 2
2
v f = vi + aDt
v 2f = vi2 + 2aDx
F = ma a =
weight : Fg = mg
Dv
Dt
g = 9.81 m
s2
ME = KE + PE
1
KE = mv 2
2
PEg = mgh
p = mv
DKE = KE f - KEi
1
PEe = kx 2
2
FDt = Dp = mv f - mvi
m1v1i + m2 v2i = m1v1 f + m2 v2 f
m1v1i + m2 v2i = ( m1 + m2 ) v f