physics first exam

A disturbance that transfers energy from place to place.

Mechanical Wave

A wave that requires a medium to travel through.

Wavelength

The distance between two corresponding parts of a wave (e.g., crest to crest).

Reflection

when a wave bounces off a surface

Diffraction

The spreading out of waves when they pass through an opening or around a barrier.

Freqeuncy unit

Hertz (Hz)

Period unit

Second(S)

Spring constant (K)  unit

Newton/meters

Mass unit

usually Kg

Gravity Number and unit

9.8 m/s²

Length(L) unit

meters

amplitude(A) unit

m, cm

Wave

A disturbance that transfers energy from place to place.

Real image

𝑑𝑖 > 0,

period

The time it takes for periodic motion to complete one cycle

wavelength unit

m/cm

speed unit

m/s

wave number unit 

K, rad/m

Angular frequency (omega) unit

W, rad/s

Phase shift unit

rad

Tension unit

N

Linear density unit

Kg/m

intensity unit

W/m²

index of infraction(n) unit 

unitless

what is the phase shift?

0 or 360, 2pi rad

what is the phase shift

270 3pi/2 

what is the phase shift 

90, pi/2 rad

how can you rearrange f=1/T to get period?

T= 1/f

The wave speed in a stretched string depends on…

tension and linear density

Waves will travel slower through strings with lower mass density

False

Waves will travel slower through strings with lower tension

True

The energy in a wave depends on which factor(s)

amplitude and frequency

Resonance

the dramatic increase in a vibrating object’s amplitude when an external source forces it to vibrate at its natural frequency (pushing at the right time on a swing 

Natural Frequency

characteristic frequency of vibration of an object

what is N in standing waves

number of anti nodes

what does this formula give you 

harmonic

what sign to use when approaching and departing

upper if approaching and lower if departing

If a light source approaches an observer, then the observed frequency is bigger than the source is called…

A blue shift 

If a light source moves away from an observer, then the observed frequency is smaller than the source

A red shift 

region of highly compressed air formed by constructive interference of sound waves when an object travels at the speed of sound

Sound Barrier

Does N2 have to be greater than N1 For TIR

Yes 

moving in the +x direction means what sign?

means - sign

focal point is ± for diverging lenses

negative

power of a lens in always in

meters 

When doing ray tracing with lenses, what is the minimum number of rays you need to find the image?

2

real image

Positive image distance

virtual image

Negative image distance

image height is _____ if inverted

negative

Magnification larger than 1

Enlarged image

positive magnification

upright image

Magnification less than 1

Reduced image

Negative magnification

Inverted image

Diverging lenses will always have……

virtual images that are upright and reduced.

for a converging lens and mirror

𝑓 > 0

for a diverging lens and mirror

𝑓 < 0

Flat mirrors produce images that are the same size as the object and …..

virtual

radius of curvature is negative for_____ mirrors

convex

Objects inside the focal length of a mirror produce images that are….

virtual, enlarged, and, upright

Images created by the eye are….

real reduced inverted

what is ideal vision

25 cm near point to infinity far point

1 over infinity equals…

0

Nearsightedness

Myopia, means can’t see far

Farsightedness

Hyperopia, means can’t see to close

To create an interference pattern that stays constant in time, the two wave sources must be…

coherent and monochromatic

what are bright spots labeled by

order (m)

if two wavelengths are 1, 2, 3, wavelengths apart, how do the waves interact?

constructive

if two wavelengths are 1.5, 2.5, 3.5, wavelengths apart, how do the waves interact?

Destructive