Law of Inertia: An object at rest tends to stay at rest and an object in motion tends to stay in motion unless acted upon by an outside force.
100
What is Friction?
A force that opposes motion.
100
What is a Force and what 2 things do you need to accurately describe one?
A push or a pull. Magnitude and Direction
100
What force is exerted by a crocodile biting down on a water buffalo with its 12kg jaws with an acceleration of 5 m/s2?
12 X 5 = 60N
100
What device did we use to measure mass?
Triple Beam Balance.
200
What is Newton's 2nd law?
Force = Mass X Acceleration
200
What type of friction affects someone swimming?
Fluid Friction.
200
What force opposes gravity?
Normal Force
200
A bullet accelerates out of a gun at 7 m/s2 with a Force of 35N. What is the mass of the bullet?
5 kg.
200
What does the slope of a speed VS time graph represent?
Acceleration
300
What is Newton's 3rd law?
For any force, there is an equal and opposite force.
300
What force/s is/are acting on a soccer ball that is rolling across the ground?
Gravity, Normal, and Friction.
300
What are the 3 basic types of physical measurements and their standard units?
Distance (meter), Mass (gram), Volume (Liter)
400
Using Newton's Laws, explain why you slam into the side of the car when it takes a sharp turn.
Inertia. You continue moving in the direction you were originally.
400
If you are pushing a book across a table at a constant velocity, is the friction force equal, less, or greater than your force? How do you know?
Equal because no acceleration.
400
What is the standard unit for Force and what does it stand for (what measurements make it up)?
Newton (N). kg X m/s2
400
One person pushes a 10kg box with a force of 50 N. Another person pushes it with a force of 30 N. How fast will the box accelerate?
8 m/s2
400
What is the equation for calculating density?
Density= Mass/Volume
500
Suppose a fly hits a windshield of a car traveling down a free-way. Newton's 3rd Law says that the windshield and fly exert the same force on each other, but the fly is crushed while the windshield is fine. Why?
The car has a much higher mass/momentum. It is also made out of much stronger materials that can handle stronger forces.
500
What is the weakest type of friction?
Fluid Friction.
500
What is the difference between weight and mass? Why do you weigh less on the moon than on Earth?
Mass is a measurement of how much matter an object has, weight is a measure of the Force applied to an object by a planet. The moon is less massive than the Earth so its gravitational pull on you is less.
500
Some people are playing a game of 4-way tug-of-war.
Team one has 2 people pulling West and they each pull with a Force of 12N
Team 2: A 50kg man accelerates .5 m/s2 to the North
Team 3: 3 people exert 8 N to the South
Team 4: 6 people each exert 5N East
What direction will they travel and what are the net forces?
6N East, 1N North
500
How many times smaller is a nanogram compared to a gram?