Advertisements
Advertisements
Question
Ultraviolet radiation has a wavelength of 300Å. If the velocity of the electromagnetic wave is 3 × 108 ms-1. Calculate:
- frequency
- time period.
Advertisements
Solution
Wavelength = λ = 300Å = 300 × 10-10 m
Velocity = v = 3 × 108 ms-1
Frequency = f = ?
Time period = T = ?
(i) We know v = λf
f = `"v"/lambda = (3 xx 10^8)/(300 xx 10^-10)`
f = `(3 xx 10^8)/(3 xx 10^-8) = 10^16` Hz
(ii) Time period = T = `1/"f"`
T = `1/10^16`
T = 10-16 s
APPEARS IN
RELATED QUESTIONS
A microphone is connected to the Y-input of a C.R.O Three different sounds are made in turn in front of the microphone. Their traces (a), (b) and (c) produces on the screen are shown in following figure.
 |
 |
 |
| (a) | (b) | (c) |
- Which trace is due to the loudest sound? Give reason for your answer.
- Which trace is due for the sound with the lowest pitch? Explain your answer.
Complete the following sentence:
Ultrasound is of frequency ___________.
Name the sound of the frequency given below:
100 Hz
A man can hear the sound of frequency :
An electromagnetic wave has a time period of 4 × 10-8 s. Calculate its frequency in MHz.
What are ultrasonic?
Does SONAR make use of infrasonic sound?
Describe a simple method to find the depth of a submerged ship.
Ultrasound has frequency of vibration
The range of audible frequency for the human ear is
