Physics Chapter 6

How does an increase increase affect acceleration?

A decrease in acceleration

Two shopping carts of equal mass are pushed by two different people. One cart accelerates three times as fast as the other cart. Describe the forces acting on each cart.

A net force acts on both carts. The net force acting on the cart that accelerates faster is 3x greater than the other force.

An object accelerates when ______

A net force acts on it

Circle the letter of each statement related to Newton's second law that is true. A. Acceleration is directly proportional to the net force B. The direction of acceleration is the same as the net force. C. Acceleration is inversely proportional to mass D. Net force and mass are always equal

A. Acceleration is directly proportional to the net force B. The direction of acceleration is the same as the net force. C. Acceleration is inversely proportional to mass

Circle the letter of each statement about freely falling objects that is true A. All fall with same acceleration B. Net force acting on them is their weight C. Weight to mass ratios are always the same D. Acceleration is g, the acceleration due to gravity.

A. All fall with same acceleration B. Net force acting on them is their weight C. Weight to mass ratios are always the same D. Acceleration is g, the acceleration due to gravity.

Look at the two books resting on a shelf in the illustration shown below. Assume the two books are identical. Circle the letter of each statement about two books that is true. A. Both books have the same mass B. Both books exert the same force on the shelf C. Both books exert the same pressure on the shelf D. Both books have the same weight.

A. Both books have the same mass B. Both books exert the same force on the shelf D. Both books have the same weight.

Circle the letter of each quantity related by Newton's second law. A. Mass B. Force C. Time D. Acceleration

A. Mass B. Force D. Acceleration

What is the formula for Newton's second law of motion?

A=f/m

Formula for acceleration

Acceleration = change in velocity/ time interval

What does Newton's second law state?

Acceleration produced by net force is directly proportional to magnitude Acceleration is the same direction of a net force Acceleration is inversely proportional to mass

What 3 things does the force of friction do?

Acts on materials that are in contact with each other Always opposes motion When on object slides against another, it must either rise over the irregular bumps or else scrap them off-requires force

Write an expression to describe the relationship between speed, area, and air resistance?

Air resistance ~ speed x frontal area

For a constant force, how does an increase in an object's mass affect its acceleration?

An increase in mass equals in a decrease in acceleration.

Circle the letter showing how mass and acceleration are related. A. Acceleration~mass B. Acceleration ~mass2 C. Acceleration~ 1/mass D. Acceleration ~1/2mass

B. Acceleration~1/mass

Circle the letter of each quantity related to pressure. A. Time B. Force C. Weight D. Area

B. Force D. Area

Circle the letter of each factor that affects the amount of air resistance experienced by an object. A. Time in contact with the air B. Speed of the object through the air C. Surface area of the object D. Weight of the object

B. Speed of the object through the air C. Surface area of the object

A 1-kg river Rock and a 10-kg small border are dropped from the back of a truck at the same time. Identify which rock would strike the ground first.

Both rocks would strike the ground at the same time

Circle the letter of each statement about force and acceleration that is true. A. Balanced forces cause constant acceleration. B. The forces acting on an object at rest are unbalanced. C. A net force acting on an object causes acceleration. D. Force is not required for an object to accelerate.

C. A net force acting on an object causes acceleration

Circle the letter that describes the unit of pressure known as a pascal. A. Newton's x area B. Newton. Meter B. Newton's per square meter D. Square meters per second

C. Newton's per square meter

For __________ force an increase in mass will result in a decrease in the acceleration

Constant

A 100N force is used to accelerate a large push cart across the floor. Circle the letter of the force required to accelerate the push cart twice as fast. A. 50 N B. 100N C. 150N D. 200N

D 200N

An object accelerates when a net force is applied to it. Circle the letter describing the conditions that would double the object's acceleration. A. Doubling the mass B. Halving the force C. Doubling the mass and halving the the force D. Halving the mass

D. Halving the mass

Circle the letter of the type of friction that causes acceleration. A. Balenced B. Negligible C. Zero D. Unbalenced

D. Unbalenced

For a constant force, an increase in the area of contact will ______ in _________

Decrease Pressure

As the area a force acts on increases, the force exerted on each unit of area ______.

Decreases

What does Newton's second law describe?

Describes relationship between mass Acceleration And net force

Acceleration is ________ proportional to net force

Directly

True or false? Friction does not depend on the types of materials n contact with each other.

False

Substances that are liquids or gasses are also called ______

Fluids

Imagine standing on a bathroom scale on two feet then one foot. Describe the force and pressure exerted in one area.

Force exerted weight- same on cases The pressure exerted though doubles when we you switch from 2 to 1

Circle the letter that best describes pressure. A. The applied force that acts on an object B. Force per unit of area C. The area to which a force is applied D. Force times surface area

Force per unit of area

A ________ is a diagram in which all the forces acting on an object are shown.

Free body diagram

An object dropped in air that experiences no air resistance is said to be in ______.

Free fall

Describe what causes friction between two solid surfaces.

Friction is due to irregularities in the two surfaces being pressed together. Force is needed to move one material up and over the other to scrap the irrgularities away.

When an object is in free fall, the only force acting on the object is

Gravity

The acceleration of an object is directly proportional to the net force acting on it. This means that, as the net force acting on the object increases, the acceleration of the object ________.

Increases

When using the equation for Newton's second law if force is measure in Newton's, then the unit for acceleration is ______ and the unit for mass is _______.

M/s2 Kg

The amount of force per unit of area is called?

Pressure

To find pressure, use the equation?

Pressure = force/area of application

Pascals

Pressure is measure in Newton's per square meter

What is the equation for pressure when the force is perpendicular to the surface area?

Pressure= force/acceleration

Identify the conditions needed for a feather and a coin to fall at the same rate

Same rate in a vacuum- no air resistance

What does air resistance force depend on?

Speed and area

Define terminal speed

Speed at which the acceleration of the falling object is 0

Define terminal velocity

Terminal speed +direction

Why do all freely falling objects fall with the same acceleration?

The net force on an object is only its weight, and the ratio of weight to mass is the same for all objects.

During a lab experiment, a net force is applied to an object and the object accelerates. The mass of the object is then doubled and the net force applied to it also doubles. Describe the objects acceleration.

The objects would accelerate at the same rate.

Is the following sentence true of false? The acceleration of an object is equal to the net force acting on it divided by the objects mass.

True

True or false? Friction depends on how much the materials come in contact with each other.

True

True or false? When friction is present an object can move with constant velocity even when an outside force is applied.

True

What 2 things does the force of friction depend on?

Types of materials How hard the surfaces press together

When a hockey puck is struck with a hockey ________ acts on the puck and the puck _________

Unbalenced forces Accelerates

Force is a ______ quanity

Vector

What does it mean for two quantities to be inversely proportional to one another?

When one quantity increases then the other will decrease.