Speed & Velocity
What is the difference between speed and velocity?
Velocity is speed in a specific direction.
What is a force?
A push or a pull.
Which of Newton's laws is also known as the law of inertia?
What is Newton's First Law?.
What is the force that opposes motion when two surfaces rub against each other?
What is friction?.
Give an example of a "push" force.
Pushing a shopping cart, pushing a door open, pushing a button, etc..
A car travels 200 miles in 4 hours. What is its average speed?
50 miles per hour.
What two forces are acting on a book resting on a table?
Gravity (downward) and the normal force (upward).
What formula expresses Newton's Second Law of Motion?
F=ma
You apply oil to a rusty hinge. Are you increasing or decreasing friction?
Decreasing friction.
Name a type of fluid friction.
Air resistance.
An object's speed is increasing. What term describes this change in motion?
Acceleration.
If a net force of 10 N is applied to a 5 kg object, what is its acceleration?
2 mls2
When you push on a wall, the wall pushes back on you with an equal and opposite force. Which of Newton's laws describes this?
What is Newton's Third Law?.
In a vacuum, will a bowling ball or a feather dropped from the same height hit the ground first?
They will both hit at the same time, because gravity affects all objects equally regardless of mass without air resistance.
What is the SI unit for force?
The Newton
What is an object's acceleration if it goes from a velocity of 0 m/s to 30 m/s in 5 seconds?
6 mls2
An object with more mass will have more of this property, making it harder to change its motion.
What is inertia?.
A small car and a large truck are moving at the same speed. Which one will require a greater force to stop?
The large truck, due to its greater mass and inertia.
What two factors affect the force of gravity between two objects?
Mass and the distance between the objects.
What is the gravitational force exerted on an object?
Weight.
Describe the motion of an object represented by a flat, horizontal line on a distance-time graph.
The object is stationary or at rest.
Define the concept of "net force."
The sum of all forces acting on an object.
Explain how Newton's Second Law of Motion applies to a baseball player throwing a ball.
The force the player applies to the ball causes it to accelerate. If the player applies more force, the ball will accelerate faster (assuming the mass stays the same).
Why do astronauts on the International Space Station feel weightless?
They are in a constant state of freefall, orbiting the Earth.
What is the difference between an object's mass and its weight?
Mass is the amount of matter in an object, while weight is the measure of the gravitational force on that object. An object's mass stays the same, but its weight can change depending on gravity.