Exam 2 5.1. Slideshow

Question 1

Δstate of motion =

Answer 1

Acceleration

Question 2

State of motion is defined by

Answer 2

Velocity

Question 3

What is Inertia?

Linear/Angular?

Equation?

Answer 3

A body to resist a change in state of motion

Linear

I = mK^2
Newtons 1st Law

To change direction, Inertia must be overcome

Question 4

NEWTON’S LAWS OF MOTION

Answer 4

• First law: Law of Inertia
• Second law: ΣF= ma
• Third law: Action/Reaction

Question 5

Newtons 1st Law: Inertia

Answer 5

A body at rest will stay at rest…
* A body in motion will stay in motion (same velocity)
UNLESS….
* A net force acts on the body

Question 6

NEWTONS 2ND LAW

Answer 6

Mass stays constant, therefore:
* a directly proportional to and in the same direction as F
* To produce a given (a), it takes a larger F for a more massive
object

Question 7

NEWTON’S 3RD LAW:
ACTION/REACTION

Answer 7

If two bodies exert forces on each other, these forces have the same magnitude but opposite directions

Question 8

Friction

Two Factors

Linear/Angular?

Answer 8

Linear

1. nature of the surfaces ()
2. force holding surfaces together

Question 9

Impulse

Answer 9

• Describes how force acts over a given time.
• Causes a change in Velocity – results in a change in Momentum
• We may want to INCREASE or DECREASE this change in velocity
  depending on the activity

Question 10

Momentum

Answer 10

Linear

• An objects moving faster will have more momentum
• A more massive object will produce more momentum than an object with less mass moving at the same velocity.

If mass is maintained, momentum is conserved

Question 11

If you apply force to an object and move it . . .

Answer 11

YOU HAVE PERFORMED MECHANICAL WORK

Units: J or Joules

Question 12

Mechanical Work

Positive work =

Negative Work =

Answer 12

Positive work = done by person on object (concentric) (Lifting, Pushing)

Negative Work = done by object on person (eccentric) (Lowering, Being Pushed)

Question 13

Energy is….

Answer 13

the capacity to do work

Chemical
Thermal
Electrical
Light
Mechanical

Question 14

Kinetic Energy is

Answer 14

the energy that a body has because it is moving
* “energy of motion”

K= 𝟏/𝟐 𝒎𝒗𝟐

Question 15

Gravitational Potential Energy

Answer 15

the energy that a body has because of its
position, relative to earth’s surface
* “potential for motion”

𝑷𝑬 = −𝒎𝒈𝒉

Question 16

STRAIN POTENTIAL ENERGY

Answer 16

Energy that has been deformed and has a tendency to return to its original position

• “potential to return to original shape”

𝑺𝑬 = 𝟏/𝟐 𝒌𝒙𝟐

Question 17

CONSERVATION
OF ENERGY

Answer 17

• the total mechanical
  energy remains
  constant if gravity is the
  only external force

Question 18

Energy: Capacity to do
work =

Answer 18

Work done by the body is EQUAL to the CHANGE IN ENERGY of body

Question 19

Work–Force is

Answer 19

Change Energy

Question 20

Five Energy’s

Answer 20

1. Chemical
2. Thermal
3. Electrical
4. Light
5. Mechanical (Kinetic + Potential)