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?