exam 3

Question 1

T/F direction of linear momentum will be opposite from direction of velocity

Answer 1

FALSE
linear momentum is in same direction as velocity

Question 2

What does a large linear momentum mean?

Answer 2

difficult to stop

Question 3

T/F conservation of momentum applies to the system

Answer 3

TRUE

Question 4

Elastic collision

Answer 4

kinetic energy is conserved
collide and exchange speed

Question 5

Inelastic collision

Answer 5

kinetic energy is NOT conserved
collide and moe together

Question 6

Glancing collision

Answer 6

after velocities have x and y components

Question 7

The center of mass of a system is the point that moves as though…

Answer 7

all the system’s mass were concentrated there
All external forces were applied there

Question 8

Where is center of mass for symmetrical object

Answer 8

at the geometric center

Question 9

When is an object in stable equilibrium?

Answer 9

If the center of mass falls inside the base of the object

Question 10

Rotation has two speeds:

Answer 10

rotational speed
linear speed- different depending on position

Question 11

Where is linear speed the fastest

Answer 11

the outer-most edge of the circle

Question 12

What direction is angular displacement positive and negative?

Answer 12

counterclockwise-positive
clockwise-negative

Question 13

Right hand rule

Answer 13

Give a thumbs up and put fingers in direction of rotation and thumb gives dircetion of omega and alpha

Question 14

Does r always equal radius?

Answer 14

NO
r= distance from the rotational axis

Question 15

A rolling object has two types of kinetic energy:

Answer 15

rotational kinetic energy
translational kinetic energy

Question 16

Positive direction of Torque

Answer 16

turning tendency of force is counterclockwise

Question 17

Negative direction of Torque

Answer 17

The turning tendency of the force is clockwise

Question 18

Two conditions of equilibrium

Answer 18

1. net external force must be zero (need to ensure mechanical and rotational equilibrium)
2. net external torque must be zero

Question 19

T/F: work-energy theorem applies to work done by torque

Answer 19

TRUE

Question 20

What is inverse square law

Answer 20

The force of gravity decreases rapidly with distance
But never comes to zero

Question 21

Keplers first law

Answer 21

All planets move around the sun in elliptical orbits

Question 22

Kepler’s second law

Answer 22

A line drawn from the sun to any planet will sweep out equal areas in equal times

Question 23

Kepler’s third law

Answer 23

the square of orbital period is proportional to cube of the average distance from sun to plane

Question 24

T/F gravitational potential energy is different at high altitudes

Answer 24

TRUE

Question 25

Escape speed

Answer 25

the speed needed for an object to escape gravity of planet/star/moon

Question 26

For pendulum motion when is velocity at max

Answer 26

when position=0 when acceleration=0

Question 27

For pendulum motion which is acceleration at max

Answer 27

at max amplitude when velocity=0

Question 28

simple pendulum

Answer 28

a point mass attached to a massless string

Question 29

physical pendulum

Answer 29

a sloid mass oscillating around its center of mass

Question 30

damped oscillation varies depending on the fluid

Answer 30

low viscocity fluid- underdamped oscillation higher viscosity fluid- critically damped oscillation even higher viscocity fluid- over damped

Question 31

underdamped oscillation

Answer 31

vibrating motion is preserved but gets smaller

Question 32

critically damped

Answer 32

object returns rapidly to equilibrium no oscillation

Question 33

over damped

Answer 33

object returns to equilibrium slowly does not oscillate

Question 34

Resonance

Answer 34

every object has natural frequencies if external frequency matches the natural frequency- amplitude will be highest object will collapse

Question 35

What is a wave

Answer 35

motion of a disturbance

Question 36

What does speed of wave depend on?

Answer 36

Properties of the medium through which it travels

Question 37

What happens when a wave reaches a boundary?

Answer 37

some or all of the wave is reflected different outcome depending on whether the end is fixed or free

Question 38

What type of waves are sound waves traveling through medium?

Answer 38

longitudinal

Question 39

How does temperature affect sound?

Answer 39

lower temp- lower speed

Question 40

Does sound travel faster or slower through solid medium?

Answer 40

generally, faster

Question 41

When is doppler effect experienced?

Answer 41

Whenever there is relative motion between the source of waves and the observer

Question 42

T/F Doppler effect is only experienced with sound waves

Answer 42

false

Question 43

What happens as sound comes towards detector?

Answer 43

higher frequency/pitch

Question 44

What happens as sound goes away from detector?

Answer 44

lower frequency/pitch

Question 45

Beats

Answer 45

alterations in loudness due to interference