Physics
Archer shoots an arrow action force is the bowstring against the arrow. The reaction force is
Arrows push against the bowstring.
A speeding truck skids to a stop if the total mass were doubled its skidding distance would
Be twice as far
When a bug hits a car window which has a greater acceleration
Bug
Rain doesn't kill you as it falls from 10,000 ft because it has a very low
Terminal velocity
The reason a tennis ball and a steel ball will accel. At same rate w/o air resistance is that
The ball with the larger force also has the larger mass
An object that is in equilibrium may be moving
True
A constant net force on an object produces constant
Velocity and acceleration
When you take a rock from earth to the moon its changes not its
Weight and mass
Accelerations are produced by
forces
Force always occurs
in pairs
How does acceleration of an object change in relation to its mass? It is
inversely proportional
If the force acting on a cart doubles what happens to the carts acceleration
it doubles
The unit of pressure is
newtons per square meter (or pascals)
An apple weighs 1 N. When held in your hand at rest above your head, the support force on the apple is
1N
An apple weights 1 N the net force on the apple when it is in free fall is?
1N
A 10N falling object encounters 4N of air resistance. The value of the net force on the object is
6N
A mass of 40 kg accelerates at 2m/s determine the net force acting on the object
80N
How much force is needed to accelerate a 2 kg physics book to an acceleration of 4 m/s 2
8N
Which of the follow would exert the most pressure on the ground.
A woman standing in high heel shoes.
Pulling a table cloth out from under a set of dishes is example of Newtons" Law
First
Since force is equal and opposite, why does a soccer ball fly off when kicked but not force
Foot has more mass
Pressure is defined as
Force per area
Pressure is known as
Force per unit area
What is the force that causes a book pushed on a desk to come to a rest
Friction
Acceleration produced by a net force is
In the same direction as the net force, directly proportional to the net force, inversely proportional to the mass
Objects move in a straight line at a constant speed because of the law of
Inertia
The acceleration of an object the applied net force
Is directly proportional to
Imagine a cart is being moved by a force. If its mass doubles what happens to acceleration
It halves
Suppose a cart is being moved by a force. If suddenly a load is dumped into the cart so that the cart's mass triples. What happens to the carts acceleration?
It is multiplied by 1/3
If the force acting on a cart triples, what happen to the cart's acceleration?
It triples
Adrian throws a rock vertically into the air. At the very top of its flight the net force is.
It's weight.
A block is dragged without acceleration in a straight line path across a level surface by a force of 6N. What is the frictional force between the block and the surface?
Less than 6N
The resultant of all the forces acting on a body is called
Net force
Rockets are unable to accelerate in space because
Nonsense rockets do accelerate in space
Friction always acts
Opposite to the objects motion
As a package falls from a stationary helicopter, its velocity increases and its acceleration
Remains the same
A truck exerts a force of 1000N on a car, accelerating it at 5m/s2 what is the cars mass
200kg
A women stands with 2 feet on a scale, the scale reads 250N when she lifts one foot, it read?
250N
A 50N falling object encounters 20N of air resistance. The net force on the object is.
30N
A jumbo jet cruises at constant velocity when the total thrust of the engines on the jet is 40,000N what is the acceleration of the jet?
40,000 m/s 2
You pull horizontally on a 50 kg crate with a force of 450 N and the friction force on the crate is 250 N. The acceleration of the crate is
5 m/s
Pared has a mass of 58kg determine his weight g=10m/s
580N
A 20N falling object encounters 15N of air resistance. The net force on the object is
5N
When an object reaches terminal velocity its acceleration is
0 m/s^2
Jon pulls on a 150 kg wagon with a constant force of 50N what is the wagon's acceleration?
0.3 m/s
A bowling ball weights 50N when held at rest in your hands, the net force on the ball is
0N
An apple weight 1 N. When held in your hand at rest above your head the net force on the apple is
0N
A 747 jet has a mass of 40,000 kg. The thrust for each of 4 engines is 12,000N what is the jets acceleration when taking off
1.2 m/s 2
A 10 kg brick and a 1 kg book are dropped in a vacuum. The force of gravity on the brick is.
10 times as much as the force on the 1 kg book
What is the mass of an object that accelerates at 2m/s with a force of 20N
10kg
A jet cruises at a constant velocity with total thrust of 15000N how much air resistance
15000N
The force of friction on an object is 15N the force needed to maintain constant velocity is?
15N
Action reaction pairs always
Acts on different objects, are equal and opposite, are in opposite direction
The hovercraft best examples newtons. Law
All three
You are on a frozen pond, and the ice starts to crack. If you lie down on the ice and begin to crawl, this will
Decrease the pressure on the ice.
The acceleration produced by a net force on an is
Directly proportional to the magnitude of the net force, in the same direction as the net force, inversely proportional to the mass of the object.
Which of the following are not an action reaction pair
Earth pulls down on apple hand pushes up on apple
A ball rolls down a 3 m tall hill and up another hill. Without friction it will go. 3m high
Equal to
A gun uses a force of 250 N on a bullet. The bullet exerts a force 250 N on the gun
Equal to
Objects with more mass have an easier time changing direction than object with less mass
False
As a ball falls the action force is pull of Earth's mass on ball. What is the reaction force
The pull of the balls mass on Earth
A F of 20N accelerates a 20kg mass by 1 m/s 2. A F of 40N accelerates a 40 kg mass by
The same
You throw a rock down. Compared to a rock that is dropped the acceleration of the thrown rock is
The same
Tennis ball and a steel ball with same size are dropped which has the greater force on it
The steel ball
Tennis ball and a steel ball with same size are dropped which has the greater acceleration on it
They both have the same acceleration
A bug flies into a car window which has a greater force
They're the same
A push on a 2 kg brick accelerates the brick. To equally accelerate a 4 kg brick, one would push?
With two times as much force.
An object has a constant mass. A constant force on the object produces constant
acceleration
