A.P. Inventory – Test 6 – Waves, Sound, and Optics
Waves and Sound

1. Sound occurs at this part of a standing wave? The antinode

2. Sound DOES NOT occur at this part of a standing wave?  The node

3. For an open pipe, sound occurs every ___1/2_________ wavelength?

4. For a closed pipe, sound occurs every ____1/4________ wavelength?

5. Open pipes play __ALL______ harmonics.

6. Closed pipes play only _ODD_____ harmonics.

7. Suppose the fundamental frequency of a resonating sound wave in a pipe is 325 Hz, What would be the next highest frequency that emits a sound in an open pipe? Closed pipe?
Open: 650 Hz
Closed: 975 Hz
 

8. If a police siren emits a sound at a frequency of 60 Hz, as it moves towards you it appears that the frequency does this? gets louder

As the car moves away? gets softer

9. What do we call the phenomenon in #8? The Doppler effect
 

10.  For a wave traveling on a string, the velocity is directly proportional to? The Tension(T)

Inversely proportional to? The linear mass density of the string(M/L)


Optics
On the Horizontal Line below, draw what would happen to an incident ray in air striking water and then refracting.

What does “n” stand for? index of refraction

“n” is a ratio of what 2 things? The speed of light in a vaccum and the speed of light in that medium

What happens to light when it enters a medium of low “n” to a medium of high “n”? The rays bend TOWARDS the normal. In other words the angle of refraction is LESS THAN the angle of incidance.

ALL ANGLES when dealing with refraction MUST be measured from the? NORMAL

If a light ray comes up from a medium of high “n” into a medium of low “n”, yet the ray does not refract you have said to have exceeded the what?
The critical angle

After you exceeded the answer above you have Total INTERNAL REFLECTION
 

A ray of light comes up from water into air. The incident angle in water is 27 degrees. Calculate the refracted angle in air.

A ray of light travels from diamond ( n = 2.36) into air. Calculate the minimum angle that would result in a refracted ray.

What is the sign of the image distance if it located in the following places?

Same side of a Converging mirror as the object? Positive

Opposite side of a Converging mirror as the object? Negative

Same side of a Converging lens as the object? Negative

Opposite side of a Converging lens as the object? Positive

What is the sign of the focal point for a Diverging Lens or Mirror? Negative

What kind of image will you have if the object is inside the focal point of a converging lens or mirror? Virtual

What kind of image will you have from a diverging lens or mirror? Virtual

An object is placed 40 cm in front of a diverging lens with a focal length of 13 cm.
a) Calculate the image distance

b) Calculate the magnification

What are the characteristics of the image mentioned above?
VIRTUAL, REDUCED, UPRIGHT

Diffraction

Bright fringes occur at every __1_____ wavelength.

Dark Fringes occur at every ___1/2____ wavelength.

The distance one ray travels more than the other is known as the? path difference

Bright fringes are a result of what type of interference? Constructive

Dark fringes are a result of what type of interference? Destructive

“d” represents: slit separation distance

“L” represents: Distance the slit is from the screen

“y” represents: Distance between the bright central and a fringe

“m” represents: the order( the numerical # of wavelengths)

The bright central has what order? ZERO

The dark fringe on each side of the bright central has what order? ZERO

If a diffraction grating has 15,450 lines per cm, what is the distance between the slits?
Convert this distance to meters, them invert.
d = 6.47 x 10-7m

What is the path difference at the 4th order dark fringe? 4 1/2λ