Vocab
The resistance of an object to changes in it's momentum and velocity.
Inertia
The force resisting the movement of a rolling object
Rolling Friction
When a car hits the breaks quickly, the passenger is thrown forward against the seatbelt.
Newton's 1st Law
Velocity x time=
Distance
Barry is walking to a friend’s house. He walks 700 meters, then realizes he walked too far. He turns around and walks 230 meters back. The entire walk takes him 21 seconds. At what speed did he walk to his friend's house?
44.29 m/s
Free Fall
Any motion of an object where just gravity is acting upon it.
The resistance created between two objects sliding against each other
Sliding Friction
When comparing a baseball and basketball thrown with the same force, the basket ball drops the quickest.
Newton's 2nd Law
Formula for speed
Total distance divided by total time
A 2,600 kg SUV run off the road at 25 m/h and collides with a tree a few meters form the road. What was the SUV's momentum?
65,000 kg⋅m/h
Frame of Reference
What 3 factors affect friction? (100 points per answer)
- Surface roughness
-Adhesion between objects
-deformations on the surface
It's easier to push a cart when you first walk in then after you've finished shopping.
Newton's 2nd Law
Mass x velocity=
Momentum
A student running track started by reaching 200m in 30s. They then ran 350m in 30s. What was their acceleration.
0.17 m/s2
Power
The amount of energy transferred/converted per unit of time. (Work/Time)
The force of friction on an unmoving object keeping it from moving
Static Friction
In a row boat, you push the paddles backwards to go forward.
Newton's 3rd Law
Formula for Acceleration
Final velocity subtracted by initial velocity divided by time
Martha is driving down 9th street, heading West. She drives 185 meters in 5 seconds at a constant speed. What is her velocity?
37 m/s West
When a external force is applied to an object that causes displacement in the direction of the force.
Work
The force that resists the motion of an object moving through or against a substance
Fluid Friction
The ball rolling across the grass slowly comes to a stop after it was kicked.
Newton's 1st Law
displacement divided by change in time =
Average Velocity
Josh dropped a softball from his second story window. The ball starts from a resting position and hits the sidewalk 1.5 s later. He calculated it to have an average acceleration of 9.8 m/s2 . What was the Final velocity?
14.7 m/s