Friction
Skis are smooth on the bottom. What does this do to the friction?
Reduce/ decrease
A cup is sitting on a table until a cat pushes it off. What Law of motion is shown?
1st Law of Motion
A box has a mass of 24 kg and a normal force of 72 N. What is the FBD?
Draw it
When something is in constant velocity, what is the acceleration?
a=0 m/s2
the tendency of an object to resist a change in its state of motion
Inertia
What would create more friction when holding a barbell?
Wearing gloves/ using chalk
Riding your bicycle. What Law of motion is shown?
2nd law of motion
A lion has a mass of 43 kg. If the cat goes into an elevator, what normal force will the lion experience when the elevator is going down with a constant velocity of 2 m/s?
FN=430N
A car accelerates from rest to a speed of 20 m/s in 5 seconds (t). What is its acceleration?
4 m/s2
the measure of the amount of matter in an object
mass
This force opposes the motion of an object that is already moving
Kinetic Friction
Explain how the 3rd Law of Motion is shown when bouncing a ball
When a ball hits the ground (action force), the ground exerts an equal and opposite force on the ball (reaction force, making it bounce back up.
A cat has a mass of 43 kg. If the cat goes into an elevator, what normal force will the cat experience when the elevator is going down with an acceleration of 3.1 m/s2?
FN=296.7N
A bike is going 9 m/s and stops in 6 seconds. What is the acceleration?
-1.5m/s2
forces that cancel each other out when acting together on a single object
balance forces
A 12 kg box is being pulled along level ground at constant velocity by a horizontal force of 38 N. What is the coefficient of kinetic friction between the box and the floor?
0.32
What force is required, to accelerate a formula 1 car weighing 642kg at 13m/s²?
8346 N
A 24 kg child enters an elevator. The elevator starts to go up starting from rest and reaches a speed of 7 m/s in 3 seconds. During this time period, what is the normal force that the child experiences?
FN=295.92N
A person with a mass of 43.7 kg is in an elevator. The normal force is 493.81 N. What is the acceleration of the elevator?
1.30 m/s2
the distance an object travels per unit of time, distance / time
speed
A 5 kg block is at rest on a surface with a coefficient of static friction of 0.6. What is the maximum force that can be applied to the block without causing it to move?
30N
Who created the 3 Laws of Motion?
Sir Isaac Newton
Draw the FBD of a person sliding down a slide
Draw it
With some wire you pull up on an 11 kg crate. You pull up on it with a normal force of 74 N. What is the acceleration of the crate as you pull it up?
a= -3.27 m/s2
the rate at which velocity changes over time; an object accelerates if its speed, direction, or both change
acceleration