Download Newton`s Laws Review

Newton’s Laws Review
Newton’s 1st
1. What is Newton’s 1st law?
An object at rest stays at rest and an object in motion stays in motion. Objects do this
because of their inertia.
2. Describe what inertia is.
Inertia is the resistance of any object to a change in its state of motion (can be moving
or motionless)
3. What must be present to overcome an object’s inertia?
FORCE
4. Give two examples of inertia.
A rock on the ground not moving until a force acts on it.
A satellite in orbiting Earth. The satellites constant velocity “inertia” keeps it in orbit
around the Earth. The Earth’s gravity causes it to go in a circular motion.
5. What is force?
Push or pull
6. What happens to an object when a force is applied to it?
Accelerates, decelerates, change direction
7. What type of force is the ground called?
Normal Force which is also called a support force.
8. What does it mean if an object in is equilibrium?
That the net force is zero. This means the object is either motionless or moving
at a constant velocity
9. Explain how an object moving at a constant velocity can be in equilibrium. Draw
a diagram of this
The applied force is equal to the frictional force.
10. What is net force?
Overall force acting on an object
11. What happens if an objects net force is unbalanced?
It will accelerate, decelerate, or change direction
12. What happens when an objects net force is equal to 0?
It will be in equilibrium, meaning it will remain at rest or at a constant speed
13. What force opposes motion?
FRICTION!!!
Newton’s 2nd Law
14. What will determine how much an object accelerates?
How much force is applied and the mass of the object
15. What unit do we use for force?
Newtons
16. What is a Newton?
1 Newton = 1 kg x 1 m/s2
17. What happens when the applied force is equal to friction?
The object will go at a constant speed and be in equilibrium
18. What are the units for:
Mass: kg
Acceleration: m/s2
Speed: m/s
Distance: m
19. What is Newton’s 2nd law of motion?
f= ma
Newton’s 3rd
23. A dictionary lying on a stationary table exerts a force of 9.8 Newtons on the table. The
force exerted on the dictionary by the table is ____ Newtons.
9.8N
24. A softball player catches a ball, the action force is the force the ball exerts against her
glove; identify the reaction force.
The glove pushing back on the ball
25. The diagram below represents a piano that is being pushed across a surface:
Which letter represents friction?
B
A↓
Applied force 
B
C↑
26. Draw an example of Newton’s 3rd Law. Label the action and reaction force.
  F2= 50 Newtons
27. F1= 28 Newtons
What is the net force of the box?
22N left
28.
Friction
Applied Force
100 kg
300N
500N
Net Force =______200N right________
29. If it takes 8N of force to keep a shopping cart rolling at a constant speed what is the
force of friction on the cart?
8N
30. When a car turns a corner is it accelerating?
YES
31. What is gravity’s acceleration? 9.8m/s2
32. Draw a picture of an object with a net force of 14 N to the left.
Force, mass, and acceleration problems.
33. If a man has a force of 576 N and an acceleration of 6.7 m/s2 what is his mass?
85.98 kg
34. A lacrosse ball is shot with a force of 87N and has a mass of .89 kg, what is the
ball’s acceleration?
2
97 m/s
35. A hockey puck is shot toward a goalie with an acceleration of 85 m/s2 and has a
mass of 1.06 kg. What force did it hit the goalie with?
90.1 N