Physics Final
An apple at rest weighs 1 N. The net force on the apple when it is in free fall is
1 N
A motorcycle of mass 100 kilograms slowly rolls off the edge of a cliff and falls for three seconds before reaching the bottom of a gully. Its momentum upon hitting the ground is
3,000 kg m/s
A bullet is fired horizontally with an initial velocity of 300 m/s from a 20-m high tower. If air resistance is negligible, the bullet hits downrange about
600 m
If gravity between the Sun and Earth suddenly vanished, Earth would continue moving in
a straight-line path
When a vertically falling firecracker bursts, the vector sum of momentum fragments
both of these
Which of the following is a scientific statement?
candy Bon Bons contain no sugar
The emphasis of the orange-and-apple sequence in your textbook is
defining systems
An educated scientific guess is a
hypothesis
Escape speed from the Moon is
much less than from Earth.
The accelerations possible for a ball on an inclined plane
range from zero to g
A fast-moving missile soaring overhead possesses
speed
When a boxer is moving away from a punch, the force experienced is reduced because
the time of contact is increased
For a scientific hypothesis to be valid, there must be a test for proving it
wrong
The net force acting on an insect falling downward at constant velocity is
zero
When a falling object has reached its terminal velocity, its acceleration is
zero
A block pulled to the left with 15 N and to the right with 5 N at the same time experiences a net force of
10 N
A motorboat that normally travels at 8 km/h in still water heads directly across a 6-km/h flowing river. The resulting speed of the boat is about
10 km/h
When a ball thrown straight upwards reaches the very top of its path, its acceleration is
10 m/s2
A push on a 1-kg brick accelerates it. Neglecting friction, equally accelerating a 10-kg brick requires
10 times as much force
A river 100 m wide flows due south at 1 m/s. A boat that travels 1 m/s relative to the water is pointed due east as it crosses from the west bank. The boat reaches the east bank
100 m farther south
The mass of a lamb that weights 110 N is about
11 kg
Consider a monkey wrench released at rest at the far edge of the solar system. Suppose that it drops to Earth by virtue of only Earth gravity. It will strike Earth's surface with a speed of about
11.2 km/s
The mass of a ball moving at 3 m/s with a momentum of 48 kg m/s is
16 kg
The circumference of a bicycle wheel is 2 meters. If it rotates at 1 revolution per second then its linear speed is
2 m/s
When you walk at an average speed of 4 m/s, in 5 s you'll cover a distance of
20 m
An object at rest near the surface of a distant planet starts to fall freely. If the acceleration there is twice that of the Earth, its speed one second later would be
20 m/s
Two projectiles are fired from ground level at equal speeds but different angles. One is fired at an angle of 30° and the other at 60°. Neglecting air resistance, the projectile to hit the ground first will be the one fired at
30 degrees
A 1000-kg automobile enters a freeway on-ramp at 20 m/s and accelerates uniformly up to 40 m/s in a time of 10 seconds. How far does the automobile travel during that time?
300 m
One half second after starting from rest, a freely falling object will have a speed of about
5 m/s
Phil leans over the edge of a cliff and throws a rock upward at 5 m/s. Neglecting air resistance, one second later the rock's speed is
5 m/s
A vertical vector of 3 units combined with a horizontal vector of 4 units has a resultant of
5 units
A toy elevator is raised from the ground floor to the second floor in 20 seconds. The power needed using 1000 J of work, is
50 W
Neglecting air resistance, a ball projected straight upward so it remains in the air for 10 seconds needs an initial speed of
50 m/s
A car's speed 3 seconds after accelerating from rest at 2 m/s 2 is
6 m/s
It is correct to say that impulse is equal to
a corresponding change in momentum
The famous Leaning Tower of Pisa doesn't topple over because its center of gravity is
above a place of support
A truly educated person is knowledgeable about
all of the above
The ram of a pile driver drops onto the top of an iron beam, driving it partway into the ground. The distance that the beam sinks into the ground depends on the
all of the above
To a fair approximation, Early Greeks knew the
all of the above
When the Sun shines on the Moon, the Moon casts a shadow
all of the above
Which of the following involves passion, talent, and intelligence?
all of the above
Facts in the field of science
are changeable
An archer shoots an arrow. Consider the action force to be the bowstring against the arrow. The reaction to this force is the
arrow's push against the bowstring
You can swing your legs to and fro more frequently when your legs are
bent
A nucleon has a mass of about
both are the same
Nellie Newton pulls her sled by a rope that is 45° to the horizontal. The horizontal and vertical components of force are
both of these
Solar power is commonly used to produce
both of these
The center of mass of a human body is located at a point that
changes as a person bends over
An open freight car rolls friction free along a horizontal track in a pouring rain that falls vertically. As water accumulates in the car, the car's speed
decreases
Nellie tosses a ball upward at an angle. Neglecting air resistance, the vertical component of the initial velocity
decreases with time to reach the top
Your pet hamster sits on a record player that has constant angular speed. If the hamster moves to a point twice as far from the center, then its linear speed
doubles
Two 2-m/s pool balls roll toward each other and collide. Suppose after bouncing apart each moves at 4 m/s. This collision violates the conservation of
energy
The force that propels a cannonball when fired from a cannon is
equal and opposite to the force the ball exerts on the cannon
A moving van with a stone lightly glued to the midpoint of its ceiling smoothly moves at constant velocity. When the glue gives way, the stone falls and hits the floor
exactly below the midpoint of the ceiling
The force that accelerates the orange and apple system featured in your textbook is actually supplied by the
floor
When we see a half Moon in the sky, the lines between Earth, Moon, and Sun
form a right triangle
The work you do when pushing a shopping cart twice as far while applying twice the force is
four times as much
An Earth satellite is simply a projectile
freely falling around the earth
Science and technology are
fundamentally different from each other
The scientific method is most effective in
gaining, organizing, and applying new knowledge
A heavy truck and a small car rolling down a hill at the same speed are forced to stop in the same amount of time. Compared with the force that stops the car, the force needed to stop the truck is
greater
When Monkey Mo is suspended at rest by holding a rope with one hand and the side of his cage with the other, all the force vectors that act on him
have a vector sum of zero
A heavy rock and a light rock of the same size are falling through the air from a tall building. The one that encounters the greatest air resistance is the
heavy rock
The lift experienced by a helicopter involves an action-reaction pair of forces between the
helicopter blades and the air
According to Kepler, the line from the Sun to any planet sweeps out equal areas of space
in equal time intervals
If you toss a coin straight upward in train that slows while the coin is in the air, the coin will land
in front of you
When the bottom string is pulled slowly in the heavy-ball-and-strings demonstration (Figure 4.8 in your book), tension
in the top string is due to your pull plus the weight of the ball
If Earth rotated more slowly about its axis, your weight would
increase
If the net force on a cart is tripled, the cart's acceleration
is three times as much
A skydiver steps from a helicopter and falls for a few seconds until terminal velocity is reached. Thereafter, until he opens his parachute, his acceleration
is zero
A single brick falls with acceleration g. The reason a double brick falls with the same acceleration is
its ratio of force to mass is the same
Galileo taught us that if you roll a ball along a level surface it will
keep rolling if friction is absent
A large heavy truck and a small baby carriage roll down a hill. Neglecting friction, at the bottom of the hill, the baby carriage will likely have
less momentum
A force is a vector quantity because it has both
magnitude and direction
A rock is thrown vertically into the air. At the top of its path the net force on it is
mg
A golf ball is thrown at and bounces backward from a massive bowling ball that is initially at rest. After the collision, compared to the golf ball, the bowling ball has more
momentum, but less kinetic energy
The Moon does not crash into Earth because
moon has a sufficient tangential speed
A ball is thrown vertically into the air. Because of air resistance, its time coming down compared to its time going up is
more
A fan attached to an ice sailcraft stalled on a windless day blows air into the sail that bounces backward upon impact. The boat
moves in the direction of the wind impact force
When Peter tosses an egg against a sagging sheet, the egg doesn't break due to
neither of these
Phil Physiker standing at the edge of a cliff throws one ball straight up and another ball straight down, both with the same speed. Neglecting air resistance, which ball hits the ground below with the greater speed?
neither, both hit with the same speed
When you and your snowboard are in motion, which of the following can be zero?
none of the above
Which of the following is NOT a mixture?
none of the above
Which of the following is a vector quantity?
none of the above
Hydrogen, like electricity, is
not an energy source
As soon as a bowling ball rolls off the edge of a table its horizontal component of velocity
remains constant
When railroad tracks make a curve, the outer track is longer. This means a wheel that rides on the outer track needs to somehow
roll faster than the wheel on the inner track
Monkey Mo hangs from the middle of a horizontal rope. Tension in the rope is greatest if the rope
sags very little
Angular momentum is greater for a satellite when it is at the
same at apogee and perigee
Galileo's use of inclined planes allowed him to effectively
slow down the ball's changes in speed
While an iron block near the Earth's surface is in free fall, it undergoes an increase in
speed
A ring, a disk, and a solid sphere begin rolling down a hill together. Which reaches the bottom first?
sphere
When no forces act on moving objects their paths are normally
straight lines
When Nellie Newton hangs at rest in the middle of a clothesline, the tension will not be the same in each side of the rope when
the angles at each side of the rope are unequal
A boy plays solitary seesaw by placing the seesaw's fulcrum one-eighth the distance from where he sits at one end. Which weighs more?
the boy
Dr. Chuck projects a ball horizontally from a lab bench. The ball lands on a bullseye marked on the floor a horizontal distance away. Compared to the time for the ball to simply drop vertically from the bench, the time in the air for Dr. Chuck's projected ball is
the same
The synthesis of a large collection of information that contains well-tested and verified hypotheses about certain aspects of the world is known as a scientific
theory
If Alex wishes to rotate his skateboard, then he must apply a
torque
Two identical arrows, one with twice the kinetic energy of the other, are fired into a bale of hay. Compared with penetration of the slow arrow, the faster arrow penetrates
twice as far
The work you do when pushing a shopping cart a given distance while applying twice as much force is
twice as much