Forces
What is a force?
A push or pull
What is the difference between balanced and unbalanced forces?
Balanced forces cancel each other out, unbalanced forces cause motion.
What are contact forces? Give two examples.
Friction, air resistance, water resistance, tension
What is mass?
The amount of matter in an object.
What is a simple machine? Name one.
A device that changes the direction or magnitude of a force; example: lever.
What does force do to an object?
Change its shape, speed, or direction
A car moves at constant speed on a straight road. Are the forces balanced or unbalanced?
Balanced
What are non-contact forces? Give two examples.
Gravity, magnetism, electrostatic
What is weight?
The force of gravity on an object.
What class of lever is a seesaw?
1st class.
What unit is used to measure force?
N
A car is slowing down to stop at a light. Are the force balanced or unbalanced?
Unbalanced
Is friction a contact or non-contact force?
What units are used to measure mass and weight?
mass - kg; weight; N
Name a simple machine that consists of a wheel with a rope or chain.
A pulley
What do we use to draw forces?
Why does a sliding book eventually stop?
Friction
How is gravity different from friction?
Gravity is a non-contact force; friction is a contact force.
Which one changes with location: mass or weight?
Weight
Which simple machine is used to split or cut objects?
Wedge
Name the two main types of forces.
Contact and non-contact.
A toy car is pushed with 10 N right, and friction is 4 N left. What is the net force and direction?
6 N
A balloon sticks to a wall after being rubbed on hair. Is this a contact or non-contact force?
Non-contact: electrostatic
Earth has a gravitational pull of 10N/kg. What is the weight of an object that has a mass of 4kg?
40 N
How does an inclined plane make work easier?
By allowing you to lift objects using less force over a longer distance.