Speed = m/s
Velocity = m/s + direction
Acceleration = m/s2
Using the white board, draw a distance vs time graph where an object is not moving/has no motion.
What is the net force on the picture below?
With air resistance being a factor, which will hit the ground first: a sheet of paper, or a crumpled sheet of paper?
Crumpled sheet of paper because the larger surface area of the sheet of paper will cause greater air resistance as it is falling compared to the crumpled sheet of paper.
Why is Newton's 1st law called the law of inertia?
Newton's first law states that objects in motion (or objects at rest) will stay in motion (or at rest) unless acted upon by an unbalanced force.
Inertia is an object's propensity to stay the same.
Speed is how fast something is moving and is measured in distance over time. Velocity is speed, but in a given direction.
Using the white board, draw a velocity vs time graph where an object has constant speed.
What is the net force for the picture below?
2N to the right
Why do you weigh more on Earth than you do on the moon?
The gravity on the moon is 1/6 that of Earth. Because weight is dependent upon the force of gravity, your weight is less on the moon.
Blowing up a balloon and letting it go demonstrates which one of Newton's Laws of Motion?
3rd
A sprinter is running a 100 m race around the track. It takes them 50 seconds to complete the race. What is their velocity?
2 m/s around the track
What can be said about Car A's acceleration vs Car B's acceleration?
Car B accelerated faster than Car A at the beginning. Car A began to decelerate at 20 seconds while Car B remained at a constant speed at 10 seconds.
______________ forces are required to change an object's velocity.
Unbalanced
Which 2 factors influence the force of gravity between 2 objects?
The objects' mass and the distance between the 2 objects
What is the net force necessary for a 160 kg car to accelerate forward at 2 m/s2?
320 N
The space shuttle Apollo was launched to an altitude of 700 km above the surface of the Earth. The shuttle travels at an average rate of 900 km/s. How long will it take for Apollo to reach its orbit?
.78 seconds
What is the speed of the object at the end of point A?
2.73 km/min
Gravity, friction, unbalanced, balanced, air resistance
Explain the difference between mass and weight.
Mass is the amount of matter in an object and does not change from place to place. Weight is depends on the force of gravity acting on the object and can change at different points on Earth, or in the universe.
A baseball accelerates downward at 9.8 m/s2 If the gravitational force acting on the baseball is 1.4N, what is the baseball's mass?
0.14 kg
A train travelling on the tracks goes from 80 mi/hr to 50 mi/hr in 0.20 hours. What is the train's acceleration?
-150 mi/hr2
What is happening at point D on this distance vs time graph?
The object is going back to it's starting position or origin.
What are the 3 types of friction? Give examples of each.
1. Sliding friction: force that opposes the motion of 2 surfaces sliding past one another. Ex: pushing a box along the floor.
2. Static friction: force between 2 surfaces that are not moving. Ex: trying to move a boulder.
3. Rolling friction: force between 2 objects rolling across each other. Ex: a skateboard on the sidewalk.
If a penny and a book are dropped from the same height, which will reach the ground first (assuming there is no air resistance). Explain why!
They will hit the ground at the same time because they are in free fall due to gravity being the only force that is acting on them. Objects, on Earth, free fall at 9.8 m/s2 regardless of mass.
Explain Newton's 2nd Law of motion. Define it, and give an example.
Newton's 2nd law of motion is F = ma. Acceleration is directly proportional to acceleration, and inversely proportional to mass. Meaning, increasing force will increase acceleration. Increasing mass will decrease acceleration.
Example: more force is required to move a bowling ball than to move a golf ball.