Intro to Force
"He drove southwest at 60 mph" is describing...
A car is making a U-turn at a constant speed of 15 mph. Is it accelerating?
Yes
If you're standing on a moving bus that stops suddenly, which way will you fall? Why?
Forward, because your body is still moving forward even though the bus has stopped.
A basketball player takes freethrows that always go slightly too high. Are their shots precise, accurate, or both?
Precise
A push or pull on an object
Force
A meteor is falling towards Earth (down) and getting faster as it falls. What is the direction of its acceleration?
Down
If hit at the same speed, which has more inertia, a ping pong ball or a baseball?
Baseball
Define hypothesis
A testable prediction
Name a key difference between mass and weight
Mass measures amount of matter in an object, does not change
Weight measures pull of gravity on an object, changes based on location
The name of the force that acted against gravity during the egg drop (hint: many of you used parachutes to maximize the impact of this force and slow down your egg)
Air resistance
Explain Newton's First Law
An object at rest tends to stay at rest, an object in motion tends to stay in motion, unless acted on by an unbalanced force.
You are doing an experiment to see how caffeine consumption affects the amount of sleep someone gets. At exactly 9 pm, you have 5 people drink no caffeine, 5 people drink 1 energy drink, and 5 people drink 2 energy drinks to see which group will get the most sleep. What is the independent variable?
Number of energy drinks consumed
Forces have direction and ______
Magnitude (how strong they are)
A biker is traveling East, but brakes as they approach a stop sign. What is the direction of their acceleration?
West
Why does a satellite in space keep moving in the same direction without needing fuel?
Once in orbit, there is no unbalanced force (such as air resistance) to change the speed or direction of the satellite, so it stays in motion
You are doing an experiment to see how caffeine consumption affects the amount of sleep someone gets. At exactly 9pm, you have 5 people drink no caffeine, 5 people drink 1 energy drink, and 5 people drink 2 energy drinks to see which group will get the most sleep. What is the dependent variable?
How much sleep/hours of sleep
Name the force that acts in the opposite direction of gravity, keeping objects on top of a surface
Normal Force
Give the equation for Newton's second law
force = mass x acceleration or
acceleration = force/mass
Give the equation for momentum
momentum = mass x velocity
You are doing an experiment to see how caffeine consumption affects the amount of sleep someone gets. At exactly 9pm, you have 5 people drink no caffeine, 5 people drink 1 energy drink, and 5 people drink 2 energy drinks to see which group will get the most sleep. Name two controlled variables in the experiment.
Type of energy drink, time that energy drink is consumed