Newton's Laws
What happens when unbalanced forces act on an object?
The object changes speed or direction.
What force pulls objects toward the center of the Earth?
Gravity.
What is kinetic energy?
Energy an object has because of its motion.
How are electric charges related to electromagnetic force?
Opposite charges attract, and like charges repel.
Which of these is an example of helpful friction? (Slipping on ice, a car’s tires gripping the road, a ball rolling forever, or a spaceship moving?)
A car’s tires gripping the road.
According to Newton’s First Law, why are seatbelts important?
They stop you from moving forward if the car stops suddenly.
Which of the following is a contact force? (Pushing a shopping cart, Gravity, Magnetism, or Static electricity?)
Pushing a shopping cart.
What is the SI unit for measuring force?
Newton.
What type of electromagnetic waves are used for communication, like radios and TVs?
Radio waves.
What happens to an object in space if no forces act on it?
It keeps moving at the same speed in the same direction forever.
How does Newton’s Third Law explain how a rocket launches?
The rocket’s engines push down, and the ground pushes it up.
How does friction affect an object's motion?
It slows the object down.
What does the Law of Conservation of Energy say?
Energy can change forms but is never lost.
Why are gamma rays dangerous?
They have very high energy and can damage cells.
What is the difference between balanced and unbalanced forces?
Balanced forces cancel each other out; unbalanced forces cause movement.
According to Newton’s Second Law, what happens if you increase the force on an object but keep the mass the same?
Acceleration increases.
Why is it harder to stop a moving truck than a moving bicycle?
Why is it harder to stop a moving truck than a moving bicycle?
What is one way heat can transfer from one object to another?
By touching (conduction)
How do electromagnets work?
An electric current flows through a wire, creating a magnetic field.
Why do astronauts float in space?
They are in free fall, so they appear weightless.
What is momentum, and why does a truck have more of it than a bicycle?
Momentum is the product of mass and velocity. A truck has more because it has more mass.
What are the four fundamental forces of nature?
Gravity, electromagnetism, strong nuclear, and weak nuclear.
How does gravity change with distance?
It gets weaker as objects move farther apart.
What is an example of an electromagnetic force in everyday life?
Using a magnet to pick up metal, electricity flowing in wires, or how a compass works.
What would happen if gravity suddenly stopped working on Earth?
Everything not attached to the ground would fly off into space!