Physical science Chapter 12 study guide
One Newton is the force that can give a mass of 1 kg an acceleration of
1 m/s2
One Newton is the force that can give an object with a mass of 1 kg an acceleration of 1 m/s2
1N=1 kg x 1m/s 2
What unbalanced force is needed to give a 976 kg vehicle an acceleration of 2.50 m/s2
2.44 x 10^3 N
Newton's ___________ law tells us how much an objects speed will be increased or decreased by an unbalanced force
2nd law of motion
What is the approximate terminal velocity of a sky diver before the parachute opens ?
320 km/h
What is the momentum of 255 g Apple falling at 16.0 m/s?
4.08 kg • m/s downward
Calculate the velocity of a 90.5 kg man running south with a momentum of 389 kg • m/s
4.30 m/s south
One pound is equal to how many Newton's ?
4.448 N
A 0.25 kg steel ball experiences a new force of 1.15 N as it rolls down a ramp. What is the acceleration of the ball ?
4.6 m/s2
How much does a 59.0 woman weigh on earth ?
578 N
A 10.0 kg dog chasing a rabbit north at 6.0 m/s has momentum of
60.0 kg m/s north
A force of 240.0 N causes an object to accelerate at 3.2 m/s2. What is the mass of the object
75 kg
Which of the following objects exerts a gravitational force ?
A bowling ball, a book, and a feather
Which is an example of projectile motion
A dart thrown at a dart board
Which statement illustrates Newton's first law ?
A stone will not move unless something pushes or pulls it, a ball rolling across the floor eventually slows down, as a car comes to a stop, the passenger sleep continue to move forward; all of the above
Which of the following is not a factor in calculating momentum
Acceleration
What happens immediately after a sky diver opens her parachute?
Air resistance greatly increases
Which statement about weight is incorrect?
An object weighs more on the moon than it weighs on Earth.
A situation known as _________ occurs when astronauts and their surroundings all accelerate at the same rate
Apparent weightlessness
Two identical cars are traveling at equal speeds, one is going north and the other south. If they collide head-on and stick together, what will happen to the motion of the cars ?
Both cars will stop
If you are given the mass of an object in pounds, the time in seconds, and the distance in feet, what must you do before you can calculate the momentum in SI units ?
Convert the mass to kilograms and convert the distance to meters
When objects are moved further apart from each other, the force of gravity between them
Decreases
When the same force is applied to two different masses, these masses will have ______ accelerations
Different
Near earths surface, the strongest gravitational force would occur between an elephant and
Earth
Whenever a force is exerted, another force occurs that is ________ in size, and ______ in direction
Equal , opposite
When you kick a stone, your foot exerts a force _________in size and ______in direction on your foot
Equal ; opposite
An example of an action-reaction pair is the action force when you jump down into a trampoline, your weight pushes down on the surface and the reaction force when the trampoline pushes back up on you with a force
Equal to your weight
The total momentum of objects before collision _______ the total momentum of the objects after collision
Equals
Orbital motion is a combination of ______ motion and freefall
Forward
When a satellite orbits earth, it experiences two motions: ________ motion and _______ toward earth
Forward ; freefall
The motion of an object resulting from only the force of gravity is _______
Free fall
What force causes a skater sliding in the ice to gradually slow down ?
Friction
Free fall is the motion of an object resulting from __________
Gravity
When an object is in free fall, the only force actions on it is
Gravity
astronauts "float" when inside on orbiting spaceship because they are
In free fall
When you stand, your weight pushes down on the ground and the ground pushes back with a force equal to your weight __________
In the opposite direction
The gravitational force on an object ________ as the objects mass increases
Increases
The tendency of an object at rest to remain a rest, or if moving, to continue moving at a constant velocity is ___________
Inertia
The tendency of an object at rest to remain at rest is
Inertia
Free-fall acceleration near earths surface
Is the same for all objects
How does the total momentum of two objects before a collision compare with the total momentum after the collision
It is the same
Which of the following units is used to measure acceleration
M/s2
According to Newton's second law of motion, force is the product of _______ and _____
Mass; acceleration
The _______ of an object remains constant while it's _______ varies according to the gravitational force it experiences
Mass; weight
Mass is measure of the amount of _______in an object
Matter
mass times velocity equals______
Momentum
When the same amount of force is applied to two different masses, the smaller mass will be accelerated _______than the larger mass
More
All ________ objects have momentum
Moving
The SI unit of force, named after the scientist who described the relationship between motion and force, is called the
Newton
The law that states that every object maintains constant velocity unless acted on by an unbalanced force is
Newton's first law of motion
The law that states that the unbalanced force acting on an object equals the objects mass times its acceleration is
Newton's second law of motion
Earth pulls on the moon and holds the mood in its orbit. The moon pulls on earth with an equal and opposite force. This is an example of...
Newton's third law
The law that states that for every action force there is an equal and opposite reaction force is
Newton's third law of motion
Near earths surface, an objects free-fall acceleration increases as its
None of above
An important safety feature in your car that is based on the concept of inertia is the
Seatbelt
As the time period of an objects momentum change becomes longer, the force needed to cause this change becomes
Smaller
Whenever an object is standing still, which value is always zero ?
Speed, velocity and momentum
When gravitational force and air resistance equalize on on object that is falling toward earth and the object stops accelerating, its velocity is called the ________ velocity
Terminal
What is the unbalanced force that slows down a ball rolling across the floor ?
The force of friction
What is the reaction force when you place a cup on a table
The force of the table on the cup
If two objects with two different masses and traveling with different velocities collide, what law allows you to predict the motion of the objects after the collision?
The law of conservation of momentum
In space, an astronaut hammers a nail. The hammer moves in one direction and the astronaut moves _____
The other direction
If an equal force is applied to two cars of equal mass, car A and car B, car A will have ______ acceleration as (than) car B
The same
Which statement about action-reaction force pairs is incorrect
They act on the same object
In the absence of air resistance, how would the acceleration of a 1.5 kg book and the acceleration of a 15 kg rock digger if the objects were dropped from the same height
They would not differ; they would be the same
An object at rest remains at rest unless it experiences a(n)
Unbalanced force
Which of the following equations is correct ?
W=mg
Which of the following is true?
Weight and mass are proportional by not equal , weight is gravitational force an object experience due to its mass, the weight of an object on earth is greater than the weight of the same object on the moon, but the objects mass stays the same
When two billiard balls collide, the total change in momentum of the balls is
Zero
Which object has the greatest inertia?
a bowling ball
When the velocity of an object changes, it is acted upon by a(n)
force
Orbital motion is a combination of
forward motion and free fall
When a moving bowling ball hits a pin, some of the ball's momentum
is transferred to the pin
Weight is best described as
the downward force exerted on objects due to gravity.
A seat belt helps you when your car stops suddenly by providing a(n)
unbalanced backward force