Physical Science Chapter 11 Sections (1-3)

A= Force divided by Mass A= 1.15 divided by 0.25 A= 4.6 m/s 2

A 0.25 kg steel ball experiences a net force of 1.15 N as it rolls down a ramp. What is the acceleration of the ball?

Unbalanced Rearward Force

A seat belt helps you when your car stops suddenly by providing a(n)?

Mass and Velocity

An object's momentum is determined by the object's?

1st: Inertia *Since the object is moving in a circular path, there must be force acting on it. 2nd: A=F divided by M *Acceleration is force divided by Mass

Apply Newton's first and second laws to explain why an object moving in a circular path at a constant speed is undergoing acceleration and has a force exerted on it.

They exert a force on each other that is Equal and Opposite.

Apply Newton's third law of motion to explain how to billiard balls moving toward each other at the same speed collide and move away from each other at the same speed as before.

Momentum= Mass x Velocity *For the train, high mass equals high momentum and the bullet has high velocity which equals high momentum.

Apply the concept of momentum to compare the mass and velocity of a slow-moving train and of a high-speed bullet.

In Free Fall

Astronauts "float" when inside an orbiting spaceship because they are?

A=F divided by M A=21 divided by 82 A= .26 m/s 2

Calculate the acceleration of a 82 kg couch that is pushed across the floor with an unbalanced force of 21 N.

Weight = Mass x Gravity (9.8 m/s 2) Mass= Weight divided by Gravity Mass= 1225 divided by 9.8 Mass= 125 kg.

Calculate the mass in kg of an object that weighs 1225 N on Earth.

F=M x A F= 1357x8 F=11,400 N.

Determine the force needed to accelerate a 1357 kg car forward at 8.0 m/s 2.

The car seat is going to stop the infants head.

Explain why a backward-facing car seat is safer for an infant than a seat that faces forward during a collision or abrupt stop.

Earth is so much larger than we are.

Explain why free-fall acceleration can be regarded as a constant for objects falling within a few hundred miles of Earth's surface.

Is the Same for all Objects

Free-fall acceleration near Earth's surface?

It is the Same

How does the total momentum of two object's before a collision compare with the total momentum after the collision?

Weight= Mass x Acceleration Due to Gravity W= 59.0 kg x 9.8m/s 2 W=528 N

How much does a 59.0 kg woman weigh on Earth?

2nd Law

Identify which of Newton's three laws of motion specifically applies in each of the following situations: A full grocery cart that is pushed starts moving and increases speed, but the same push increases its speed even more when the cart is empty.

1st Law

Identify which of Newton's three laws of motion specifically applies in each of the following situations: A meteor moving in a straight path changes direction when it flies by Earth.

2nd Law

Identify which of Newton's three laws of motion specifically applies in each of the following situations: A skateboard moves FASTER in the same direction it is pushed.

3rd Law

Identify which of Newton's three laws of motion specifically applies in each of the following situations: You feel a force against the sole of your foot as you take a step forward.

A. If distance is the same go for the more massive object.

Identify which pair of objects would have greater gravitational force between them in the examples below. Use the law of universal gravitation to explain your answers.

The Same

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.

Mass

Increasing which of these conditions results in more gravitational force between two objects?

Momentum= Mass x Velocity Momentum= 500 x 64 M=32000 Momentum= 1000 x 32 M=32000

Indicate which of the following has greater momentum: a 500 kg car moving at 64 km/h, or a 1000 kg truck moving at 32 km/h. Justify your answer.

Momentum= Mass x Velocity If the mass does not change, then velocity is CONSTANT.

Infer what you can say about the velocity of a car that is moving with a constant momentum.

Yes

Interpret the following situations to determine whether an object's velocity is being altered by an applied force. (answer Yes or No) A batter hits a baseball upward into right field.

Yes

Interpret the following situations to determine whether an object's velocity is being altered by an applied force. (answer Yes or No) A falling book lands on the floor with a pre-collison speed of 9 m/s.

Yes

Interpret the following situations to determine whether an object's velocity is being altered by an applied force. (answer Yes or No) A satellite orbits Earth at a CONSTANT speed of 7000 m/s.

No

Interpret the following situations to determine whether an object's velocity is being altered by an applied force. (answer Yes or No) A submarine moves due east at a CONSTANT speed of 45 m/s.

1 m/s 2

One Newton is the force that can give a mass of 1 kg an acceleration of?

Forward Motion and Free Fall

Orbital motion is a combination of?

It should have an arc / curve

Predict the path of the cannon ball below. To do this, draw a line in the direction of the cannon ball's flight. Also draw and label the horizontal and vertical components of the cannon ball's projectile motion.

Reaction Force

The force exerted on the racket by a hit tennis ball is the?

Distance Between Objects

The gravitational force between two objects depends on masses of objects and?

Both Cars will Stop

Two identical cars are travelling with equal speeds. One is going north and the other south. They collide head-on and stick together. How will the cars react after the collision?

An object with high mass has high inertia.

Use the concept of inertia to illustrate why volleyball is not played with a ball that has a mass similar to a bowling ball.

Friction

What force causes a skater sliding on the ice to gradually slow down?

Momentum= Mass x Velocity M= .255 x 16.0 M= 4.08 kg m/s Downward

What is the momentum of a .255 g apple falling at a 16.0 m/s?

Force=Mass x Acceleration Force= 976 x 2.50 Force= 2.44 x 103 N

What unbalanced force is needed to give a 976 kg vehicle an acceleration of 2.50 m/s 2?

Is Transferred to the Pin

When a moving bowling ball hits a pin, some of the ball's momentum?

Gravity

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

Equal, Opposite

Whenever a force is exerted, another force occurs that is __________in size, and ________ in direction.

All of the Above

Which Statement illustrates Newton's first law? *Inertia 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 passengers continue to move forward.

A Dart Thrown at a Dart Board

Which is an example of projectile motion?

A Bowling Ball

Which object has the greatest inertia?

A newspaper lying on a table

Which of the following has a momentum of zero *Something NOT moving?

All of the above

Which of the following objects exerts a gravitational force? A bowling ball a feather a book

They Act on the Same Object

Which statement about action-reaction force pairs is incorrect? They act on the same object. They always occur in pairs. They occur at the same time. They are equal and opposite.

An object weighs more on the moon that it weighs on Earth.

Which statement about weight is incorrect? An object weighs more on the moon that is weighs on Earth. A change in an object's location can change the object's weight. An object's weight is directly proportional to its mass. The weight of an object depends on gravity.

56 N acting on a 1-kg Box

Which will result in the greatest acceleration? 56 N acting on a 1-kg box 23 N acting on a 2-kg box 56 N acting on a 2-kg box @3 N acting on a 5-kg box