Newton

1
Newtons Laws of MotionReview

• Chapters 4-6
• November 9/10

2
Question

• When a balloon deflates, the balloon pushes on
  the air and _______.

3
Answer

• The air pushes on the balloon

4
Question

• Object one has twice as much mass as another
  object. Object one also has twice as much _____

5
Answer

• Inertia

6
Questions

• When all the forces acting on an object are
  balanced and the net force is zero, the object is
  said to be in ___________.

7
Answer

• Equilibrium

8
Questions

• Accelerations are produced by

9
Answer

• Forces

10
Question

• A book weighs 4 N. When held at rest in your
  hands, the net force on the book is ____.

11
Answer

• Zero

12
Question

• Which has a greater mass, a kilogram of feathers
  or a kilogram of steel?

13
Answer

• The both have the same mass, 1 kg

14
Question

• As a ball falls, the action force is the pull of
  Earth's mass on the ball. What is the reaction to
  this force?

15
Answer

• The pull of the balls mass on the Earth

16
Question

• The outside force that often slows objects down
  or stops their motion is ___.

17
Answer

• Friction

18
Question

• If you push off the ground with a force of 500 N
  when you jump upward, what force pushes Earth
  downward?

19
Answer

• 500 N according the Newtons 3rd law

20
Question

• What is the pressure exerted on a table by a book
  that weighs 35 N and covers an area of 3 m2?

21
Answer

• Known
• F 35 N
• A 3 m2
• Unknown
• P
• Equation
• P F
• A

Solve P 35 N 3m2 P 11.67 N/m2
or 11.67 Pa
22
Questions- honors

• With what acceleration does an 65 kg box move if
  it is pushed 155 N?

23
Answer

• Known
• m 65 kg
• F 155 N
• Unknown
• a ?
• Equation
• F ma

Solve F ma 155N (65kg)a 155 (65kg)a 65kg
65kg 2.38 m/s2
24
Question

• A dog walks on a street. What is the force of
  friction between the 225 N dog and the street
  that has a coefficient of friction of 0.26?

25
Answer

• Known
• w 225 N FN
• µ 0.26
• Unknown
• Ff ?
• Equation
• Ff µFN

Solve Ff µFN Ff (0.26)(225N) Ff 58.5 N
26
Question

• Force and accelerations are ______________
  proportional.

27
Answer

• Directly proportional
• More force results in more acceleration

28
Question

• Mass and acceleration are __________________
  proportional.

29
Answer

• Inversely proportional
• More mass results in less acceleration
• Less mass results in more acceleration

30
Question

• Pressure and Area are _______________
  proportional.

31
Answer

• Inversely proportional
• More area covered results in less pressure
• Less area covered results in more pressure

32
Question

• Which has greater tangential speed, a horse near
  the outside rail of a merry-go-round or a horse
  near the inside rail?

33
Answer

• The one on the outside because it has a larger
  radius

34
Question

• Which has greater rotational speed, a horse near
  the outside rail of a merry-go-round or a horse
  near the inside rail?

35
Answer

• They both have the same rotational speed

36
Question

• According the Newtons law of universal
  gravitation, what is the relationship between
  force and distance

37
Answer

• Inverse squared

38
Questions

• In what direction does centripetal force pull?

39
Answer

• Inward / toward the center of the circle

40
Question

• If centripetal force is taken away, what will
  happen to the object moving in the circle?

41
Answer

• The object will fly off tangent (in a straight
  line)

42
Question
The gravitational force between two massive
spheres
a. is always an attraction.
b. depends on how massive they are.
c. depends inversely on the square of the distances between them.
d. all of the above
43
Answer
The gravitational force between two massive
spheres
a. is always an attraction.
b. depends on how massive they are.
c. depends inversely on the square of the distances between them.
d. all of the above
44
Question

• Gravitational forces are the weakest forces found
  in nature. Because of this _____.

a. the gravitational effect between a pencil and Earth cannot be seen
b. there is no gravitational force between two 1-kg masses
c. gravitational forces that are easily observed involve one or more large masses
d. there is no movement between two large masses located near each other in space  
45
Answer

• Gravitational forces are the weakest forces found
  in nature. Because of this _____.

a. the gravitational effect between a pencil and Earth cannot be seen
b. there is no gravitational force between two 1-kg masses
c. gravitational forces that are easily observed involve one or more large masses
d. there is no movement between two large masses located near each other in space