CK-12 Chapter 10

Which of the following are equivalent to 1 Newton?

0.225 pounds

Xander's friend Corey has a skateboard that he rides at Newton's Skate Park. The combined mass of Corey and his skateboard is 60 kg. At the top of his jump, the net force acting on him is 30 Newtons. What is his acceleration at that moment?

0.5 N/kg

One Newton is the force needed to cause a

1-kg object to accelerate at 1 m/s2

If a 50-kg person is running at a rate of 2 m/s, the person's momentum is _____ kg⋅m/s

100

If a person has a mass of 7.00 kg on Earth, what will be his weight on the Moon? (The acceleration due to gravity on the moon is 1.635 m/s2.)

11.5 N

The weight of a cart with a mass of 150 kg is ___ N. (Use 9.8 m/s2 for the acceleration due to gravity.)

1470

The mass of an object on Earth is 100 kg. Assuming the acceleration due to gravity on the moon is exactly one-sixth of the acceleration due to gravity on Earth, what is the weight of the object on the moon?

163 N

Calculate the force acting on a body whose linear momentum changes by 10 kg m/s in 5 seconds.

2 N

A 15N net force is used to move a 5 kg box. What is the resulting acceleration?

3 m/s2

Find the missing velocity (x) in the diagram of a vehicle collision seen in the following figure so that momentum is conserved.

4 m/s

In the diagram below, a 60 kg roller skater pushes a 30 kg roller skater with a force of 5 N. The force exerted by the 30 kg roller skater on the 60 kg roller skater is ___ N.

5

Xander's friend Corey has a skateboard that he rides at Newton's Skate Park. What net force would have to act on Cory who has a mass of 60 kg for him to have an acceleration of 1 m/s2?

60 N

Which object has the greatest inertia?

8-kg bowling ball

All objects on Earth accelerate downward due to gravity at a rate of _____ m/s2

9.8

The mass of an object on Earth is 100 kg. What is the weight of the object on Earth?

980 N

Which of the following is true about the action-reaction forces encountered in Newton's third law?

Always act on different objects

To calculate an object's weight on Earth from its mass, substitute its mass (in kilograms) for m in the formula F=?

F=m x 9.8 m/s2

All objects with mass have momentum. (TRUE OR FALSE?)

False

f you run into a curb on a skateboard, you will fall forward off your skateboard because there is an unbalanced force applied to your body. (TRUE OR FALSE?)

False

The SI unit for force is the

Newton

What is the SI unit for weight?

Newton

Which of the following football players have the same momentum?Ted: mass = 60 kg, velocity = 2.0 m/s Todd: mass = 80 kg, velocity = 1.7 m/s Tom: mass = 90 kg, velocity = 1.5 m/s Tim: mass = 100 kg, velocity = 1.2 m/s

Ted and Tim

Action and reaction forces never cancel each other. (TRUE OR FALSE?)

True

An object in motion will stay in motion, while an object at rest will stay at rest unless acted on by a net force. (TRUE OR FALSE?)

True

Forces always act in pairs. (TRUE OR FALSE?)

True

Newton's first law of motion is also called the law of inertia. (TRUE OR FALSE?)

True

Once an object starts moving, inertia keeps it moving without any additional force being applied to the object. (TRUE OR FALSE?)

True

______________ is a measure of the force of gravity pulling down on an object. It is measured in newtons (N), the common unit for measuring force.

Weight

What is the equation for calculating the acceleration of an object when its mass and the net force acting on it are known?

a= f/m

Equal and opposite forces that act on the same object are called ______________ forces.

balanced

Without an unbalanced force acting on it, a moving object will keep going with ___________ speed in the same direction.

constant

Newton's _________ law of motion states that an object at rest will remain at rest and an object in motion will stay in motion unless it is acted on by an unbalanced force.

first

When hit from behind in a car crash, a passenger can suffer a neck injury of whiplash. This is an example of Newton's ______ law.

first

The force of _____ opposes the motion of all objects moving through or across other matter.

friction

Which force counteracts motion whenever two surfaces come into contact?

friction

The tendency of an object to resist a change in its motion is called ____________.

inertia

What is the tendency of an object to resist a change in its motion?

inertia

While riding a skateboard, Nina ran into a rough patch of pavement, but she thought she could ride right over it. Instead, the skateboard stopped but Nina didn't. Her ________ kept her moving forward, so she fell off the skateboard.

inertia

What is the SI unit for momentum?

kg x m/s

The SI unit for acceleration is

m/s2

For a given net force, an object will accelerate less if it has a greater

mass

The inertia of an object depends on its _____.

mass

The inertia of an object is greater when it has greater _______.

mass

Factors that determine an object's momentum include its

mass and velocity

Complete the sentence using word momentum, velocity or acceleration. The property of a moving object that makes it hard to stop is ______________________.

momentum

________________________ is a property of a moving object that makes it hard to stop

momentum

The equation for calculating momentum from mass and velocity

momentum=mass×velocity

The reaction to an action is always equal in strength and in the _____________________ direction to the action

opposite

Newton's _________ law of motion states that every action has an equal and opposite reaction.

third

When a bat strikes a ball, the force exerted can send the bat backwards. The force exerted on the bat is due to Newton's __________ law

third

Whenever an action and reaction occur, momentum is

transferred

Inertia causes a resting object to remain at rest and a moving object to remain in motion unless a(n) _______ force acts on the object.

unbalanced

Momentum is a product of mass and ____________.

velocity