Physics-
General
Easy
Question
An object producing a pitch of 400 Hz flies past a stationary person. The object was moving in a straight line with a velocity
. What is the change in frequency noted by the person as the person as the object files past him?
- 1440 Hz
- 240 Hz
- 1200 Hz
- 960 Hz
The correct answer is: 1200 Hz
From Doppler’s effect, the perceived frequency (v’) is given by
Where 
is velocity of observer, 
of source, v of sound and v the original frequency.
Given, 
(stationary), 
Related Questions to study
Physics-
A police car moving at 
, changes a motorcyclist. The police man sounds his horn at 176 Hz, while both of them move towards a stationary siren of frequency 165 Hz. Calculate the speed of the motorcycle, if it is given that he does not observe any beats.
A police car moving at , changes a motorcyclist. The police man sounds his horn at 176 Hz, while both of them move towards a stationary siren of frequency 165 Hz. Calculate the speed of the motorcycle, if it is given that he does not observe any beats.
Physics-General
Physics-
A motor cycle starts from rest and accelerates along a straight path at 
. At the starting point of the motor cycle gone when the driver hears the frequency of the siren at 94% of its value when the motor cycle was rest? (Speed =330 
)
A motor cycle starts from rest and accelerates along a straight path at . At the starting point of the motor cycle gone when the driver hears the frequency of the siren at 94% of its value when the motor cycle was rest? (Speed =330 )
Physics-General
Physics-
A piston fitted in cylindrical pipe is pulled as shown in the figure. A tuning fork is sounded at open end and loudest sound is heard at open length 13cm, 41 cm and 69 cm, the frequency of tuning fork if velocity of sound is 
is
A piston fitted in cylindrical pipe is pulled as shown in the figure. A tuning fork is sounded at open end and loudest sound is heard at open length 13cm, 41 cm and 69 cm, the frequency of tuning fork if velocity of sound is is
Physics-General
Physics-
An open organ pipe is closed suddenly with the result that the second overtone of the closed pipe is found to be higher in frequency by 100 than the first overtone of the original pipe. Then the fundamental frequency of the open pipe is
An open organ pipe is closed suddenly with the result that the second overtone of the closed pipe is found to be higher in frequency by 100 than the first overtone of the original pipe. Then the fundamental frequency of the open pipe is
Physics-General
Physics-
In an experiment with sonameter a tuning fork of frequency 256 Hz resonates with a length of 25 cm and another tuning fork resonates with a length of 16 cm. tension of the string remaining constant the frequency of the second tuning fork is
In an experiment with sonameter a tuning fork of frequency 256 Hz resonates with a length of 25 cm and another tuning fork resonates with a length of 16 cm. tension of the string remaining constant the frequency of the second tuning fork is
Physics-General
Physics-
A uniform wire of length L, diameter D and density S is stretched under a tension T. the correct relation between its fundamental frequency f, the length L and the diameter D is
A uniform wire of length L, diameter D and density S is stretched under a tension T. the correct relation between its fundamental frequency f, the length L and the diameter D is
Physics-General
Physics-
If you set up the seven overtone on a string fixed at both ends, how many nodes and antinodes are set up in it?
If you set up the seven overtone on a string fixed at both ends, how many nodes and antinodes are set up in it?
Physics-General
Physics-
If in a resonance tube a oil of density higher than that water is used then at the resonance frequency would
If in a resonance tube a oil of density higher than that water is used then at the resonance frequency would
Physics-General
Physics-
Two vibrating tuning forks produce progressive waves given by 
. Number of beats produced per minute is
Two vibrating tuning forks produce progressive waves given by . Number of beats produced per minute is
Physics-General
Chemistry-
Silica reacts with magnesium compound X, X reacts with dil HCl and forms Y and Z If two moles of HCl reacts with one mole of X then how many mole of y will be formed
Silica reacts with magnesium compound X, X reacts with dil HCl and forms Y and Z If two moles of HCl reacts with one mole of X then how many mole of y will be formed
Chemistry-General
Chemistry-
Carbondioxide is used for extinguishing fire because
Carbondioxide is used for extinguishing fire because
Chemistry-General
Chemistry-
Which is correct regarding CO2
Which is correct regarding CO2
Chemistry-General
Chemistry-
CO2and N2are non-supporters of combustion However for putting out fires CO2 is preferred over N2 because CO2
CO2and N2are non-supporters of combustion However for putting out fires CO2 is preferred over N2 because CO2
Chemistry-General
Chemistry-
The correct statement with respect to CO is
The correct statement with respect to CO is
Chemistry-General
Chemistry-
Which element can form the most acidic oxide
Which element can form the most acidic oxide
Chemistry-General
