Transcript Physics Review #1

Physics Review #1
LCHS
Dr.E
A girl leaves a history classroom and
walks 10 meters north to a drinking
fountain. Then she turns and walks 30
meters south to an art classroom. What is
the girl’s total displacement from the
history classroom to the art classroom?
(A) 20 m south
(B) 20 m north
(C) 40 m south
(D) 40 m north
One car travels 40 meters due east in 5.0
seconds, and a second car travels 64
meters due west in 8.0 seconds. During
their periods of travel, the cars definitely
had the same
(A) average velocity
(B) total displacement
(C) change in momentum
(D) average speed
A skater increases her speed uniformly
from 2.0 m/s to 7.0 m/s over a distance of
12 meters. The magnitude of her
acceleration as she travels this 12 meters is
(A) 1.9 m/s2
(B) 2.2 m/s2
(C) 2.4 m/s2
(D) 3.8 m/s2
A ball thrown vertically upward reaches
a maximum height of 30 meters above
the surface of Earth. At its maximum
height, the speed of the ball is
(A) 0.0 m/s
(B) 3.1 m/s
(C) 9.8 m/s
(D) 24 m/s
Which object has the most inertia?
(A) a 0.001-kilogram bumblebee
traveling at 2 meters per second
(B) a 0.1-kilogram baseball traveling at
20 meters per second
(C) a 5-kilogram bowling ball traveling
at 3 meters per second
(D) a 10-kilogram sled at rest
A child kicks a ball with an initial velocity of 8.5 meters per
second at an angle of 35º with the horizontal, as shown. The
ball has an initial vertical velocity of 4.9 meters per second
and a total time of flight of 1.0 second.
The horizontal component of the ball’s initial velocity is
approximately
(A) 3.6 m/s (B) 4.9 m/s (C) 7.0 m/s (D) 13 m/s
A child kicks a ball with an initial velocity of 8.5 meters per
second at an angle of 35º with the horizontal, as shown. The
ball has an initial vertical velocity of 4.9 meters per second
and a total time of flight of 1.0 second.
The maximum height reached by the ball is approximately
(A) 1.2 m
(B) 2.5 m
(C) 4.9 m
(D) 8.5 m
A ball of mass M at the end of a string is
swung in a horizontal circular path of radius
R at constant speed V. Which combination
of changes would require the greatest
increase in the centripetal force acting on
the ball?
(A) doubling V and doubling R
(B) doubling V and halving R
(C) halving V and doubling R
(D) halving V and halving R
A box is pushed toward the right across a
classroom floor. The force of friction on
the box is directed toward the
(A) left
(B) right
(C) ceiling
(D) floor
A 40-kilogram mass is moving across a
horizontal surface at 5.0 meters per
second. What is the magnitude of the net
force required to bring the mass to a stop
in 8.0 seconds?
(A) 1.0 N
(B) 5.0 N
(C) 25 N
(D) 40 N
What is the speed of a 1.0×103-kg car that
has a momentum of 2.0×104 kg•m/ s
east?
(A) 5.0 × 10–2 m/s
(B) 2.0 × 101 m/s
(C) 1.0 × 104 m/s
(D) 2.0 × 107 m/s
If the speed of a car is doubled, the
kinetic energy of the car is
(A) quadrupled
(B) quartered
(C) doubled
(D) halved
A 1-kilogram rock is dropped from a cliff
90 meters high. After falling 20 meters,
the kinetic energy of the rock is
approximately
(A) 20 J
(B) 200 J
(C) 700 J
(D) 900 J
A student does 60 joules of work pushing a
3.0-kilogram box up the full length of a
ramp that is 5.0 meters long. What is the
magnitude of the force applied to the box to
do this work?
(A) 20 N
(B) 15 N
(C) 12 N
(D) 4.0 N
A boat weighing 9.0 × 102 Newtons
requires a horizontal force of 6.0 × 102
Newtons to move it across the water at
1.5 × 101 meters per second. The boat’s
engine must provide energy at the rate of
(A) 2.5 × 10–2 J
(B) 4.0 × 101 W
(C) 7.5 × 103 J
(D) 9.0 × 103 W
A high school physics student is sitting in
a seat reading this question. The
magnitude of the force with which the
seat is pushing up on the student to
support him is closest to
(A) 0N
(B) 60 N
(C) 600N
(D) 6,000 N
The diagram above represents a 5.0-N
force and a 12-N force acting on point P.
The resultant of the two forces has a
magnitude of
(A) 5.0-N (B) 7.0-N (C) 12-N (D) 13-N
What does the slope of this graph represent?
(A) impulse
(B) momentum
(C) speed
(D) power
A ball dropped from rest falls freely
until it hits the ground with a speed of
20 m/s. The time during which the
ball is in free fall is approximately
(A) 1 s
(B) 0.5 s
(C) 2 s
(D) 10 s
In a 4.0-kilometer race, a runner
completes the first kilometer in 5.9
minutes, the second kilo- meter in 6.2
minutes, the third kilometer in 6.3
minutes, and the final kilometer in 6.0
minutes. The average speed of the runner
for the race is approximately
(A) 0.16 km/min
(B) 0.33 km/min
(C) 12 km/min
(D) 24 km/min
A golf ball is hit with an initial velocity
of 15 m/s at an angle of 35 degrees above
the horizontal. What is the vertical
component of the golf ball’s initial
velocity?
(A) 8.6 m/s
(B) 9.8 m/s
(C) 12 m/s
(D) 15 m/s
A 60-kg rollerskater exerts a 10-N force
on a 30-kg rollerskater for 0.20 second.
What is the magnitude of the impulse
applied to the 30-kg rollerskater?
(A) 50 N•s
(B) 2.0 N•s
(C) 6.0 N•s
(D) 12 N•s
A 10-kilogram block is at
rest on a plane inclined at
15° to the horizontal.
As the angle of the incline is increased to
30°, the mass of the block will
(A) decrease
(B) increase
(C) remain the same
If the direction of a moving car changes
and its speed remains constant, which
quantity must remain the same?
(A) velocity
(B) displacement
(C) momentum
(D) kinetic energy
Two carts are pushed apart by an
expanding spring. If the average force on
the 1-kilogram cart is 1 newton, what is
the average force on the 2-kilogram cart?
(A) 1 N
(B) 0.5 N
(C) 0.0 N
(D) 4 N
A lab cart is loaded with different masses
and moved at various velocities. Which
diagram shows the cart-mass system with
the greatest inertia?
A sled and rider slide down a
snow-covered hill that makes
an angle of 30° with the
horizontal. Which vector best
represents the direction of the
normal force, FN, exerted by the hill on the sled?
What is the gravitational potential energy
with respect to the surface of the water
of a 75.0-kg diver located 3.00 m above
the water?
4
2.1710
(A)
J
3
(B) 2.2110 J
2
(C) 2.2510 J
1
(D) 2.2910 J
A 60.0-kilogram runner has 1920 joules
of kinetic energy. At what speed is she
running?
(A) 5.66 m/s
(B) 8.00 m/s
(C) 32.0 m/s
(D) 64.0 m/s
The diagram shows points A, B, and C at or
near Earth’s surface. As a mass is moved from
A to B, 100 joules of work are done against
gravity. What is the amount of work done
against gravity as an identical mass is moved
from A to C?
(A) 100 J (B) 173 J (C) 200 J (D) 273 J
Which pair of graphs represents the same
motion of an object?
The vector diagram
represents two forces,
F1 and F2, simultaneously acting on an
object. Which vector best represents the
resultant of the two forces?
An egg is dropped from a third-story
window. The distance the egg falls from
the window to the ground is closest to
0
10
(A)
m
1
(B) 10 m
2
(C) 10 m
3
(D) 10 m
The diagram above shows a
5.00-kilogram block at rest
on a horizontal, frictionless table Which
diagram best represents the force exerted
on the block by the table?
On a highway, a car is driven 80
kilometers during the first 1.00 hour of
travel, 50 kilometers during the next 0.50
hour, and 40 kilometers in the final 0.50
hour. What is the car’s average speed for
the entire trip?
(A) 45 km/h
(B) 60. km/h
(C) 85 km/h
(D) 170 km/h
Which quantity is a vector?
(A) impulse
(B) speed
(C) power
(D) time
A high-speed train in Japan travels a distance
of 300 kilometers in 3.60 × 103 seconds. What
is the average speed of this train?
(A) 1.20 × 10–2 m/s
(B) 12.0 m/s
(C) 8.33 × 10–2 m/s
(D) 83.3 m/s
A 25-Newton weight falls freely from
rest from the roof of a building. What is
the total distance the weight falls in the
first 1.0 second?
(A) 19.6 m
(B) 9.8 m
(C) 4.9 m
(D) 2.5 m
A golf ball is given an initial speed of 20
m/s and returns to level ground. Which
launch angle above level ground results in
the ball traveling the greatest horizontal
distance? [Neglect friction.]
(A) 60°
(B) 45°
(C) 30°
(D) 15°