Frequency

Q.

How do you calculate the period and frequency?

Q.

Voice of which of the following is likely to have a minimum frequency?

1. Baby girl

2. Baby boy

3. A man

4. A woman

Q.

How is ultrasound useful in the medical field?

Q.

What is the most fundamental property of a wave?

1. Temperature

2. Pressure

3. Frequency

4. Wavelength

Q. Time taken to complete one oscillation is called _______.

1. frequency
2. wavelength
3. time period
4. amplitude

Q.

What is the relationship between wavelength and frequency?

1. Linear

2. Inverse

3. There is no relation between wavelength and frequency.

4. None of these

Q. the characteristic that will remain unaltered as light moves from one medium to another is ?
1. Velocity
2. Wave length
3. Frequency
4. None of these

Q.

Explain why strings of different thicknesses are provided on a stringed instrument.

Q.

The wavelength of waves produced on the surface of water is 20 cm. If the wave velocity is 24 m $s^{-1}$, calculate :

(i) the number of waves produced in one second,

(ii) the time in which one wave is produced.

Q.

The magnitude of the maximum disturbance in the medium on either side of the mean value is called____.

1. Frequency

2. Amplitude

3. Time period

4. Wavelength

Q.

A wave source produces $20$ crests and $20$ troughs in $0.2sec$. Find the frequency of the wave.

1. 500 Hz

2. 100 Hz

3. 300 Hz

4. 200 Hz

Q.

Mention two properties of a wave; the property which varies and the other which remains constant when a wave passes from one medium to another.

1. Property which varies: Speed (or velocity) and Wavelength
   Property which remains constant: frequency

2. Property which varies: Speed (or velocity) and frequency
   Property which remains constant: Wavelength

3. Property which varies: Wavelength
   Property which remains constant: Speed or velocity and frequency

4. Property which varies: Wavelength and frequency
   Property which remains constant: Speed or velocity

Q.

State one way of increasing the frequency of a note produced by an air column.

Q.

(a) Name one factor on which the frequency of sound emitted due to vibrations in an air column depends.

(b) How does the frequency depend on the factor stated in part (a).

Q.

What is the relationship between wavelength and frequency for a sound wave moving at a constant speed?

1. Inverse

2. None of these

3. There is no relation between wavelength and frequency.

4. Linear

Q.

Name the factors on which sound frequency of a string instrument depends.

Q.

State the factors on which frequency of sound produced by a string instrument depends.

Q.

How is the frequency of sound varied in the three types of musical instruments?

Q.

A sound travels at a speed of $339m{s}^{-1}$. If its wavelength is $1.5cm$, then find out the frequency of the sound wave.

Q.

What do you understand by the pitch of a sound?

Q. The frequency of a source of sound is
$100Hz$. The number of sound wave produced in one minute is

1. $6000$
2. $600$
3. $1000$
4. $100$

Q.

The SI unit of frequency is ……………….

Q.

A wave source produces $20$ crests and $20$ troughs in $0.2$ sec. Find the frequency of the wave.

1. 100 Hz

2. 500 Hz

3. 200 Hz

4. 300 Hz

Q.

The frequency of a source of sound is $100Hz$. How many times does it vibrate in a minute?

1. 1000 times

2. 6000 times

3. 100 times

4. 600 times

Q.

Before playing the orchestra in a musical concert, a sitarist tries to adjust the tension and pluck the string suitably. By doing so, he is adjusting

1. the intensity of sound only

2. the amplitude of sound only

3. frequency of the sitar string with the frequency of other musical instruments

4. loudness of sounds

Q. Time period varies _______ with/of the frequency.

1. linearly
2. inversely
3. as the square
4. exponentially

Q.

(a) What are radioisotopes? Give examples.
(b) How are they produced?
[5 MARKS]

1. f

Q. What do you understand by the term Pitch in relation to sound waves?

Q.

A stretch wire 0.4m long is made ot vibrate in two different modes as shown. What is the wavelenght of wave in

i) mode P

ii) mode Q

and

iii) IN which case the note is of higher pitch

1. i) 0.4m (ii) 0.2m (iii) Q

2. i) 0.4m (ii) 0.4m (iii) Q

3. i) 0.8m (ii) 0.4m (iii) Q

4. i) 0.4m (ii) 0.2m (iii) P

Q. Calculate the time taken by a sound wave of frequency 1000 Hz and wavelength 50 cm to travel a distance of 500 m.

1. 1 s
2. 6 s
3. 3 s
4. 12 s