Why is air resistance considered a form of friction
Front
because it is in contact with air particles
Back
The displacement -2m north represents what positive displacement in which direction?
Front
south
Back
When a horse pulls on a cart, the cart pulls on the horse with an equal but opposite force. How is the force able to pull the cart?
Front
The horse and car are not in equilibrium
Back
what quantity describes the difference between an objects initial positions and the objects final position?
Front
displacement
Back
the cars engine is doing work on the car, yet the kinetic energy of the car is not changing. What is happening to the energy applied by the engine.
Front
energy is converted to another form
Back
explain the scientific meaning of work?
Front
transfer of conversion of energy
Back
How are force vectors represented in force diagrams?
Front
by arrows
Back
If two teams playing tug of war on opposite forces, what is the net external force on the rope?
Front
zero
Back
what formula can be used to calculate work if the force acts at an angle to the displacement?
Front
w= f x d x cos()
Back
how is work related to force and displacement?
Front
the greater the distance the more work
Back
In the equation EF=ma what is the direction of the acceleration?
Front
positive
Back
The length of a vector arrow in a diagram is proportional to what property of the vector?
Front
magnitude
Back
The length of the force vector is proportional to what property of a force?
Front
magnitude
Back
is the quantity ( vi/a) a scalar quantity or a vector quantity?
Front
vector
Back
How can you use the Pythagorean theorem to add two vectors that are not perpendicular?
Front
Make it a right triangle/ perpendicular
Back
name the SI units for work
Front
joules
Back
What is the SI unit of acceleration?
Front
m/s^2
Back
What is a projection of a vector along an axis of a coordinate system called?
Front
components
Back
What is a resultant?
Front
the result of adding to vectors
Back
why does it require much less force to accelerate a low mass object that it does to accelerate a high mass object the same amount?
Front
tendency to resist acceleration = inertia
Back
what happens to an object in motion when it experiences a nonzero net external force?
Front
Being accelerated
Back
what is the term for the curved parabolic path that an object follows when thrown, launched or otherwise projected near the surface of the Earth?
Front
projectile
Back
The ratio of the change in an objects velocity to the time required for the change to occur describes what quantity
Front
acceleration
Back
is work a vector quantity or a scalar quantity
Front
vector
Back
State Newton's first law
Front
object at rest will remain at rest until acted upon by an unbalanced force.
Back
The Newton is the SI unit of what physical quantity?
Front
Force
Back
What is a vector quantity?
Front
a quantity with magnitude and direction
Back
In the equation form of Newton's second law, EF=ma what does EF represents sum of forces?
Front
sum of forces
Back
Breaking a vector into two components is given what term?
Front
resolving
Back
air exerts a force on a leaf as it falls from a tree. Is the work done on the tree positive , negative, or zero?
Front
negative
Back
Describe the initial state of motion of a bicyclist whose motion is described by equation vf^2=2ax
Front
vi^2 is zero
Back
The amount of force equal to 1 kg/ms^2 defines what SI unit?
Front
I Newton of Force
Back
what must be true about the acceleration for the equation vavg=(vi+vf)/2 to be valid
Front
acceleration has to be constant
Back
Describes the forces acting on a car as it moves along a level highway in still air at a constant speed.
Front
ground resistance on car, force, and gravity
Back
in this text what does the symbol uk represent?
Front
coefficient
Back
what is a free fall?
Front
when something falls due to the force of gravity
Back
Do action-reaction pairs result in equilibrium?
Front
yes
Back
what is the ratio of an objects displacement to the time interval during which the displacement occurred?
Front
average velocity
Back
Why is force not a scalar quantity?
Front
because it has magnitude and direction.
Back
What term is used to describe the vector sum of all the forces acting on an object?
Front
net force
Back
What is a scalar quantity?
Front
has no magnitude or direction/ average speed
Back
How does the theory of field forces explain how Objects could exert forces on each other without touching?
Front
a fields interaction w/ one another
Back
Describes the graph of the horizontal component of velocity versus time for the motion of the ball shown in the figure above.
Front
acceleration at a constnt velocity/ straight line
Back
For an object to be in equilibrium the bet force acting on the object must have what value?
Front
must be equal to zero
Back
When a falling object reaches terminal speed what is the relationship between Fr, air resistance, and Fg?
Front
gravity and friction are equal
Back
what happens to air resistance when an object accelerates?
Front
air resistance is going to increased
Back
Distinguish between mass and weight.
Front
mass= no gravity
weight= with gravity
Back
what is the net work done on the car over a distance of 250m?
Front
zero because the car is in constant speed
Back
Which is a vector distance or displacement?
Front
displacement
Back
as a car drives down the road are any forces doing work on the car?
Front
friction gravity
Back
Section 2
(46 cards)
how are work and power related?
Front
directly proportional
Back
what is Kepler's first law of planetary motion?
Front
planets travel in elliptical motion
Back
list 3 different forms of mechanical energy.
Front
kinetic, gravitational and elastic
Back
explain how energy, time and power are related.
Front
p=w/t, work is a change in kinetic energy
Back
describe how the collision affects the total momentum and total kinetic energy of the system?
Front
kinetic energy decreases total kinetic add to zero.
Back
state in words, the law of conservation of momentum for an isolated system.
Front
the total momentum of all objects interacting with one another remains constant regardless of nature of the forces by the way the object moves.
Back
What is a term for the quantity f is an applied force and t is the time interval over which force is applied?
Front
impulse
Back
describe the relationship between kinetic energy and gravitational potential energy doing the free fall of pencil from a desk.
Front
kinetic grows as potential reduces when reduces when it falls.
Back
a ball is whirled in a horizontal circular path on the end of a string. predict the path of the ball when the string breaks.
Front
straight until acted upon by gravity due to inertia
Back
Is kinetic energy a vector or scalar quantity?
Front
scalar quantity
Back
in terms of energy what occurs when a machine does work on an object?
Front
power
Back
almost all collisions in the everyday world are of what type?
Front
inelastic
Back
explain how an object moving at a constant speed can have a nonzero acceleration.
Front
tension force
Back
what quantity is the sum of kinetic energy and all forms of potential energy in a system?
Front
Mechanical energy
Back
why is the sound produced by a collision evidence that the collision is not perfectly elastic?
Front
producing sound requires energy
Back
an ice skater initially skating at 3 m/s speeds up to a velocity of 5 m/s. How does the momentum of the skater change?
Front
the skater's momentum increases
Back
is it possible for a space ship traveling with constant velocity to experience a change in momentum?
Front
yes
Back
State in words the work kinetic energy theorem.
Front
the network done by all forces acting on an object is equal to change in an objects KE
Back
a tether ball is tied to a string and whirled in a horizontal circular path at a constant speed. what causes the ball and string to move away from the post?
Front
tension is centripetal force
Back
as a bullet travels through the air it slows down due to air resistance. How does the bullet's momentum change as a result?
Front
momentum decreases as speed decreases
Back
Tow objects move separately after colliding and both total momentum and total kinetic energy remain constant. identify the type of collision.
Front
elastic
Back
a large moving ball collides with a small stationary ball. Describes how the momentum of each ball change.
Front
larger ball momentum decreases and small ball momentum increase.
Back
compare the gravitational force the sun exerts on earth to the gravitation force the earth exerts on the sun.
Front
both accelerate toward each other
Back
what provides the centripetal force for the moon's orbit around earth?
Front
gravitation
Back
a force is applied to stop a moving shopping cart. how would increasing the time interval change the force required.
Front
p=ft, it decreases the distance the cart
Back
how is a machine's power rating related to its rate of doing work on an object?
Front
p=w/t the rate at which work is done
Back
two objects stick together and move with the same velocity after colliding. Identify the type of collision.
Front
perfectly inelastic
Back
what provides the centripetal force for a car driving on a circular track?
Front
friction
Back
write an equation for momentum.
Front
p=mv
Back
does the apple accelerate towards earth or does the earth accelerate toward the apple.
Front
they accelerate toward each other
Back
what form of energy is stored in any stretched or compressed object?
Front
potential energy
Back
is power a vector or scalar quantity?
Front
scalar
Back
what is the magnitude of the gravitational force the apple exerts on the earth?
Front
1
Back
what form of energy is associated with the position of an object in Earth's gravitational field.
Front
gravitational energy
Back
is there an outward force in circular motion?
Front
no
Back
what does the wattage of a light bulb indicate?
Front
how much electricity the bulb has
Back
describe briefly how the moon causes tides on earth.
Front
the moon causes oceans to bulge
Back
how can a small force produce a large change in momentum?
Front
if the force acts on an object long enough
Back
are astronauts in orbit weightless?
Front
no
Back
what provides the centripetal force for a ball whirled on a string?
Front
string
Back
after colliding objects are deformed and lose some kinetic energy. identify the type of collision.
Front
inelastic
Back
what is the significance of the word universal in Newton's Law of universal gravitation.
Front
gravitation exists all throughout the universe
Back
discuss the following statement: a satellite is continually in free fall.
Front
parallel to earth, projectile motion
Back
what is Kepler's third law of planetary motion?
Front
t^2=(4pi^2/gm)r^2
Back
what is Kepler's second law of planetary motion?
Front
planets rotate around the axis
Back
Negative work is done on a moving object. How does the kinetic energy of the object change?