Download Review sheet for - The Russell Elementary Science Experience

Review Sheet for
Speed and Velocity
I. Vocabulary
1. Position is an object’s place or location
2. Speed is a measure of the distance an object moves in a given amount of time.
a. Example: A boy takes 1 second to travel 2 meters or 2 meters per seconds.
0 seconds
1 second
Total distance = 2 meters
3. An objects speed in a particular direction is its velocity.
2 meters per second going east
0 seconds
1 second
Total distance = 2 meters
2 meters per second to the west
4. When an object starts, stops, speeds up, slows down, or turns left or right, it changes velocity. Any change in velocity is called acceleration.
5. Momentum is a measure of how hard it is to slow down or stop an object. It is a product of an object’s velocity and its mass.
a. Example: Which would be harder to stop? Which would have more momentum?
Semi-Truck going at 50 m/hr
or a Compact Car going 50 m/hr
Semi-Truck going 30 m/hr
or a Semi-Truck going 50 m/hr
6. The property of matter that keeps it moving in a straight line or keeps it at rest is called inertia.
6 Newton’s Second Law
7. Newton’s Third Law
Possible Questions
1. What is the difference between speed and velocity? The only difference is that velocity adds direction to distance over time, while speed only shows the
relationship of a distance traveled over a certain period of time.
2. If two objects have the same velocity but different masses, which object has the greater momentum? The object with the greater mass will have a greater
momentum.
3. If two objects have the same mass but different velocities, which object has the greater momentum? The object with the greater velocity will have a
greater momentum.
4. Who was the scientist who introduced the three laws of Motion? Isaac Newton was the scientist who introduced the three laws of Motion.
5. Will an object in motion that is moving in a straight line continue to move that way forever? If not, why not? Probably not, because sooner or later some
force will act on it, changing its motion is some way.
6. What does Newton’s first law state? An object at rest will remain at rest, and an object in motion will continue moving in a straight line at a constant
speed until an outside force acts on it?
7. What does Newton’s second law state? An object’s acceleration depends on the size and direction of the force acting on it and on the mass of the object.
8. What does Newton’s third law state? For every action, there is an equal and opposite reaction.
9. What factors affect acceleration? The size of the force, the direction of the force; the mass of the object
10. How does the size of the force affect acceleration? A large force will cause more acceleration than a small force.
11. How does the mass of an object affect acceleration? The greater the mass of an object the greater the forced required to accelerate it.
III. Be able to identify in which direction an object will go if a force with a certain amount of force and direction is applied to it.
Bonus Questions
Be able to work out problems dealing with speed and velocity and acceleration.
Speed: A truck driver is driving to work. He travels a distance of 30 miles in 3 hours. What is the truck driver’s average speed?
Find speed by dividing the distance traveled by the time it took to travel the distance. 30miles divided by 3 hours = 10 miles per hour
Velocity: A truck driver is driving to work. He travels a distance of 30 miles in 3 hours going towards the east. What is the truck driver’s velocity?
Find velocity by dividing the distance traveled by the time it took to travel the distance and add the direction: 30miles divided by 3 hours = 10 miles per hour
to the east.
Acceleration: A truck driver is driving to work. When he first got on the expressway, his velocity was 60 miles per hour to the east. He had to get off the
freeway and changed his velocity to 30 miles per hour to the east. What was the acceleration?
Acceleration: To find acceleration, just subtract the ending velocity by the beginning velocity: 60 m/h – 30 m/h = 30 m/h