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is exactly equal in magnitude to the action force.

Wherever there is an action force, there must be a reaction force which

the wall "kicks you back" with the same force as your have exerted on it

Why does your foot hurt when you kick a wall?

pushes Jack equally hard even without waking up

Jack pushes Jill, who is asleep. Jill

Question 5 answers

Question 5 answers

force that the ball exerts on the bat

A player hits a ball with a bat. The action force is the impact of the bat against the ball. The reaction to this force is the

exerts the same amount of force on the bat

When a bat hits a ball, the ball simultaneously

equal to your weight

When you stand still on the ground, how large of a support force does the ground exert on you?

the air

A lift force on a helicopter is exerted by

friction force between the tires and the pavement.

The force that moves the car along the road is exerted by the

small car

A massive fast-moving car collides head-on with a light slow-moving car. The acceleration is greater on the

the Moon and the Earth pull with the same force on each other

The Earth pulls on the Moon. Similarly, the Moon pulls on the Earth, How do their pulls compare to each other?

the Moon's acceleration is larger

The Earth pulls on the Moon. Similarly, the Moon pulls on the Earth, How do their accelerations compare to each other?

Volkswagen -- Due to 2nd Newton's law (a = F/m), the acceleration is greater on the light car (Volkswagen). And due to kinematic equation for velocity (refer to Chapter 3 - Kinematics) the change in velocity is directly proportional to the acceleration: "Change in v" = at.

A heavy Mack truck and a light Volkswagen traveling at the same speed have a head-on collision. The vehicle that undergoes the greatest change in velocity will be

twice as fast

For the same force (the carts influence each other with the forces which are equal in magnitude) on half a mass results in twice the acceleration (2nd Newton's law), and greater acceleration means greater velocity

For the same force (the carts influence each other with the forces which are equal in magnitude) on half a mass results in twice the acceleration (2nd Newton's law), and greater acceleration means greater velocity

Two carts, one having a twice bigger mass than another, roll away from each other when the compressed spring that joins them is released. How fast does the lighter cart roll compared with the heavier cart?

100 N

A rope is pulled by two people in a tug-of-war. Each pulls with 100 N of force. What is the tension force in the rope?

pushes harder on the ground to produce greater friction force from the ground

The team that wins a tug-of-war is the team that

even if the pulling forces between the horse and a wagon are equal, there is still an unbalanced force on the wagon. Friction exerted on the horse by the ground is greater than friction exerted on the cart's wheels by the ground.

A horse exerts a pulling force on a heavy wagon. The wagon pulls back on the horse with an equal force. The wagon still accelerates (rolls forward) because