Newton's Second Law Physics Quiz retake

A 10-N falling object encounters 10 N of air resistance. The magnitude of the net force on the object is___

0N

An apple weighs 1 N. When held at rest above your head, the net force on the apple is___

0N

When an object reaches terminal velocity its acceleration is___

0m/s/s

Suppose a particle is accelerated through space by a constant 10-N force. Suddenly the particle encounters a second force of 10-N in a direction opposite to that of the first force. What happened to the particles speed and acceleration?

Continues at the speed it had when it encountered the second force

As Bob falls from a high-flying stationary helicopter, his velocity increases and his acceleration___

Decreases

A steel ball and a wood ball of the same size are released together from the top of a tower. In the absence of air resistance they both would reach the ground at the same time. The reason for this is that the force on each ball is the same. (true or false)

False

It is possible for an object in free fall (no air resistance) to have zero acceleration. (true or false)

False

The acceleration of an object is inversely proportional to the net force acting on it. (true or false)

False

The speed of an object dropped in air will continue to increase without limit. (true or false)

False

What are accelerations produced by?

Forces

If the force acting on a cart doubles, what happens to the cart's acceleration?

It doubles

Suppose a cart is being moved by a force. If suddenly a load is dumped into the cart so that the cart's mass doubles, what happens to the cart's acceleration?

It halves

How does acceleration of an object change in relation to its mass?

It is inversely proportional

A rock is thrown vertically into the air. At the very top of its trajectory the net force on it is___

It's weight

Compared to its weight on earth, a 10-kg object on the moon will weigh___

Less

A tennis ball and a solid steel ball the same size are dropped at the same time. In the absence of air resistance, which ball has the greater acceleration?

Nonsense! They both have the same acceleration

The reason a tennis ball and a solid steel ball will accelerate at the same rate, in the absence of air resistance, is that___

The ball with the larger force also has the larger mass

A heavy person and a light person parachute together and wear the same size parachutes. Assuming they open their parachutes at the same time, which person reaches the ground first?

The heavy person

A force of 1N accelerates a mass of 1 kg at the rate of 1 meter per second squared. The acceleration of a mass of 2 kg acted upon by a force of 2 N is___

The same

Aunt Minnie throws a rock downward, and air resistance is negligible. The acceleration of the rock compared to being dropped is___

The same

A tennis ball and a solid steel ball the same size are dropped at the same time. Which ball has the greater force acting on it?

The steel ball

A tow truck exerts a force of 3000 N on a car, accelerating it at 2 m/s/s. What is the mass of the car?

1,500kg

A 10-kg brick and a 1-kg book are dropped in a vacuum. The force of gravity on the 10-kg brick is___

10 times as much as the force on the 1-kg book

A girl whose weight is 200 N hangs from a bar supported by two vertical strands of rope. What is the tension in each strand?

100N

Suppose the force of friction on a sliding object is 10 N. The force needed to maintain a constant velocity is___

10N

How much force is needed to accelerate a 2-kg physics book to an acceleration of 6 m/s/s?

12N

An apple weighs 1 N. The net force on the apple when it is in free fall is___

1N

A car has a mass of 1000 kg and accelerates at 2 meters per second per second. What is the magnitude of the force acting on the car?

2,000N

If you pull horizontally on a crate with a force of 150 N and the crate doesn't move, the friction force must be 150 N. Now if you pull with 250 N so the crate slides at constant velocity, the friction force is___

250N

A 747 jumbo jet has a mass of 30000 kg. The thrust for each of four engines is 15000 N. What is the jet's acceleration when taking off?

2m/s/s

A girl pulls on a 10-kg wagon with a constant force of 30 N. What is the wagon's acceleration?

3m/s/s

A jumbo jet cruises at a constant velocity when the total thrust of the engines on the jet is 40,000 N. How much air resistance acts on the jet?

40,000N

You pull horizontally on a 50-kg crate with a force of 500 N, and the friction force on the crate is 250 N. The acceleration of the crate is___

5m/s/s

A 10-N falling object encounters 4 N of air resistance. The magnitude of the net force on the object is___

6N

A block is dragged without acceleration in a straight-line path across a level surface by a force of 6 N. What is the frictional force between the block and the surface?

6N

An object has a constant mass. A constant net force on the object produces constant___

Acceleration

The combination of all the forces that act on an object is called the net force. (true or false)

True

The force that supports the weight of a book lying at rest on a tabletop is called a normal force. (true or false)

True

A push on a 1-kilogram brick accelerates the brick. Neglecting friction, to equally accelerate a 10-kilogram brick, one would have to push___

With 10 times as much force