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Lesson 1
Lesson 2
Lesson 3
Lesson 4
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100
What is speed?
The distance traveled in a certain time.
100
What is inertia?
The tendency of objects to stay in motion or to stay still
100
What is gravity?
A force that acts to pull pairs of objects together.
100
What is friction?
A force that resists the movement of one surface past another surface.
100
How does the mass of an object affect the way it moves?
The greater the mass the greater the force of gravity between it and another object. The higher the mass the more force required to move it, so the object with less mass will move farther/faster.
200
What is the formula for speed?
Speed=distance/time
200
What is needed to overcome inertia?
Force
200
What is mass?
The amount of matter in an object.
200
How does friction affect the way objects move?
Friction slows the movements of objects.
200
If you weigh 100 lbs on Earth, about how much would you weigh on the moon? Why is it different?
16 2/3 lbs, on the moon you're only 1/6 of your weight
300
How is velocity different than speed?
Velocity is a measure of speed in a certain direction.
300
What is an example of inertia? Explain?
Seat belts-help people from continuing to move forward when a vehicle stops quickly.
300
What is weight?
The measure of the amount of force that gravity exerts on you.
300
What are two ways to reduce friction? How?
oil, grease, water; They make surfaces slip more easily across each other, reducing friction.
300
Explain how friction is related to tires in the winter.
The ice/snow cause a lack of friction for tires and that is why cars slide on the ice/snow.
400
What is a way to cause a change in velocity?
Slow down, speed up, or change direction.
400
How do forces work in pairs?
When a force pushes one direction another force always pushes with equal strength in opposite direction.
400
If you shoot an arrow into the air, why doesn't its inertia just keep it going in the same direction?
Gravity caused by the Earth's mass eventually pulls the arrow toward the ground.
400
How does air resistance affect the way objects move?
Air resistance pulls on objects, slowing them down.
400
What is an example of air resistance?
Parachute, bike, etc.
500
What is the speed of a tractor driving 500 km for 2 hours?
250km/hr
500
If a frog pushes backward on the leaf and a leaf pushes forward on the frog, causing the frog to move forward and the leaf to move backward, what is the action force and the reaction force?
Action: frog pushing backward Reaction: leaf pushing forward. What is this called?
500
What is acceleration?
The rate of change in speed or direction of movement.
500
What is one way to reduce air resistance (think about a jet plane)?
Streamline: to design smooth, rounded surfaces on an object so it slips through the air, with the least possible resistance.
500
If you drop a soccer ball and bowling ball at the same moment from the top of a tall building, which one would fall faster?
They would fall at the same rate. Their acceleration would be the same because gravity makes all objects fall at the same rate near the Earth's surface.