1st Law
What is another name for the 1st last of motion?
Law of Inertia
What is the equation used to determine force in the 2nd law of motion?
F=m x a
State the 3rd Law of Motion.
For every action, there is an equal and opposite reaction.
These 2 things affect the momentum of an object.
Mass & speed
A push or a pull
Force
740.5 dg = ? kg
0.07405 kg
Which has more inertia? Why?
Basketball or bowling ball
Bowling Ball, greater mass
Which would be easier to accelerate? Why?
Baseball, golf ball, or bowling ball
A golf ball, it has the smallest mass.
A Newton is equivalent to what units?
kgm/s2
Calculate the momentum of a 1200kg car with a velocity of 25 m/s.
30000 kgm/s
A force that always resists motion
Friction
The amount of air resistance is affected by this.
The surface area of the object
One similarity and one difference between friction and inertia
Similarities: Can both resist movement, increase with more mass
Differences: Inertia can keep things moving, friction always stops them; Friction is a force
Force is measured in what unit?
Newton (N)
Name two ways to increase the amount of friction between two objects?
Change the surface, increase the mass
The parking brake on a 1200kg car has broken and the vehicle reached a momentum of 7800 kgm/s. What is the velocity of the car?
6.5 m/s
The downward force all objects experience on earth.
Gravity
What is terminal velocity? What 2 forces affect it?
Gravity & Air Resistance
What does an unbalanced force result in?
A change in motion
A 500kg truck accelerates from 0 m/s to 5 m/s in 5 seconds. How much force is required to move the truck?
500 N
a=(5m/s-0m/s)/5s = 1m/s2
F=500kg x 1m/s2
A 200N force propels a bullet forward. What force does the bullet apply to the gun?
200N
A bowling ball moving at 6.2m/s generates 52 kgm/s of momentum. What is the mass of the ball?
8.39kg
What are the two types of friction?
Static & Kinetic
You drop a ball out a window and it takes 5 sec to hit the ground. What was its velocity when it hit?
49m/s
v = g x t = 9.8m/s2 x 5s
Explain the difference between inertia and momentum.
Intertia wants objects to continue doing what they're doing, both still and moving.
Momentum only causes objects to want to keep moving.
What force is needed to accelerate a 2000kg car from a speed of 25 m/s to 40 m/s in 5 seconds?
6000 N
a=(40m/s-25m/s)/5s = 3m/s2
F=2000kg x 3m/s2
Give a real-life example of Newton’s 3rd law.
A bat hits a ball and the ball pushes back on the bat
You jump off the floor and the floor pushes back up on you
Etc.
A deer with a mass of 57kg escaped a wolf with a mass of 63kg by running at 13m/s. The wolf just missed because he only ran at 12.5m/s. Who had more momentum?
The wolf (787.5 kgm/s)
(Deer had 741 kgm/s)
A moving object's mass and velocity determine this?
Momentum
What two factors affect the amount of gravitational force?
Mass of the objects and distance between objects