8.25.R - Lesson Review: Need for Speed / Interference

Question 1

Sound travels in the medium of air at about ____________.
760 meters per second
186,000 miles per second
300,000 kilometers per second
340 meters per second
300 meters per second
340 miles per second

Answer 1

340 meters per second

Question 2

Select two things that lightning travels through.
wood
cardboard
carpet
dirt
plumbing
sand
wires

Answer 2

plumbing
wires

Question 3

How many seconds between lightning and thunder mean the strike is one mile away?
3 sec
1 sec
10 sec
9 sec
5 sec
6 sec

Answer 3

5 sec

Question 4

The loud explosive noise a plane makes when we hear the shock wave that comes from it when it is traveling at or above the speed of sound is called ______________.
refraction
a sonic boom
amplitude
inertia
the Doppler effect
the sound barrier

Answer 4

a sonic boom

Question 5

What is the metric unit for measuring the frequency of sound waves?
watts
minutis
amps
newtons
hertz

Answer 5

hertz

Question 6

An antinode is _____________.
the halfway point between nodes
the end of a wave
the part of a wave that does not move
the beginning of a wave

Answer 6

the halfway point between nodes

Question 7

What kind of interference do you get if you have two speakers playing music in a room where the crests meet?
constructive
rarefaction
reflection
destructive
dissonance
resonance

Answer 7

constructive

Question 8

What do we call it when a transverse wave overtakes another wave, and the force of both waves is added together in a larger wave?
a longitudinal wave
destructive interference
constructive interference
resonance
rarefaction
a compressed wave

Answer 8

constructive interference

Question 9

When two crests from two wave sources meet, what is it called?
anticrest
crest
trough
supercrest
antinode
ultracrest

Answer 9

supercrest

Question 10

Plucking a guitar string and watching the string vibrate with the wave appearing not to move down the string is a good example of __________.
a standing wave
a compressed wave
destructive interference
rarefaction
a longitudinal wave
constructive interference

Answer 10

a standing wave

Question 11

What measurements are necessary for calculating speed? Please respond in 1–2 complete sentences using your best grammar.

Answer 11

Your Answer:
The measurements needed will be distance and time.

Question 12

The formula for speed is Total Distance / Total Time. Based on the data table below, what is the average speed after 2 minutes? Please show all calculations.

Time (min.) Distance (m)

0 0

1 50

2 75

3 90

Answer 12

Your Answer:
Total distance / total time

75m / 2min= 37.5

the answer is 37.5