Doppler Effect
WAVES

173107 With what velocity should an observer approach stationary sound source so that the apparent frequency of sound appear to be double of the initial frequency?
(given velocity of sound $=v$ )

1 $\mathrm{v}_{0}=\mathrm{v} / 2$
2 $\mathrm{v}_{0}=3 \mathrm{v}$
3 $\mathrm{v}_{0}=2 \mathrm{v}$
4 $\mathrm{v}_{0}=\mathrm{v}$
WAVES

173108 An object producing a pitch of $400 \mathrm{~Hz}$ flies past a stationary person. The object was moving in a straight line with a velocity $200 \mathrm{~m} / \mathrm{s}$. The velocity of sound is $300 \mathrm{~m} / \mathrm{s}$. What is the change in frequency noted by the person as the object flies past him?

1 $1440 \mathrm{~Hz}$
2 $240 \mathrm{~Hz}$
3 $1200 \mathrm{~Hz}$
4 $960 \mathrm{~Hz}$
WAVES

173109 The frequency of a radar is $780 \mathrm{MHz}$. The frequency of reflected wave from aeroplane is increased by $2.6 \mathrm{kHz}$. Velocity of the aeroplane is

1 $0.25 \mathrm{~km} / \mathrm{sec}$
2 $0.5 \mathrm{~km} / \mathrm{sec}$
3 $1.0 \mathrm{~km} / \mathrm{sec}$
4 $2 \mathrm{~km} / \mathrm{sec}$
WAVES

173110 A whistle of frequency $540 \mathrm{~Hz}$ rotates in a horizontal circle of radius $2 \mathrm{~m}$ at an angular speed of $15 \mathrm{rad} / \mathrm{s}$. The highest frequency heard by a listener at rest with respect to the centre of circle (velocity of sound in air $=330 \mathrm{~ms}^{-1}$ )

1 $590 \mathrm{~Hz}$
2 $594 \mathrm{~Hz}$
3 $598 \mathrm{~Hz}$
4 $602 \mathrm{~Hz}$
WAVES

173107 With what velocity should an observer approach stationary sound source so that the apparent frequency of sound appear to be double of the initial frequency?
(given velocity of sound $=v$ )

1 $\mathrm{v}_{0}=\mathrm{v} / 2$
2 $\mathrm{v}_{0}=3 \mathrm{v}$
3 $\mathrm{v}_{0}=2 \mathrm{v}$
4 $\mathrm{v}_{0}=\mathrm{v}$
WAVES

173108 An object producing a pitch of $400 \mathrm{~Hz}$ flies past a stationary person. The object was moving in a straight line with a velocity $200 \mathrm{~m} / \mathrm{s}$. The velocity of sound is $300 \mathrm{~m} / \mathrm{s}$. What is the change in frequency noted by the person as the object flies past him?

1 $1440 \mathrm{~Hz}$
2 $240 \mathrm{~Hz}$
3 $1200 \mathrm{~Hz}$
4 $960 \mathrm{~Hz}$
WAVES

173109 The frequency of a radar is $780 \mathrm{MHz}$. The frequency of reflected wave from aeroplane is increased by $2.6 \mathrm{kHz}$. Velocity of the aeroplane is

1 $0.25 \mathrm{~km} / \mathrm{sec}$
2 $0.5 \mathrm{~km} / \mathrm{sec}$
3 $1.0 \mathrm{~km} / \mathrm{sec}$
4 $2 \mathrm{~km} / \mathrm{sec}$
WAVES

173110 A whistle of frequency $540 \mathrm{~Hz}$ rotates in a horizontal circle of radius $2 \mathrm{~m}$ at an angular speed of $15 \mathrm{rad} / \mathrm{s}$. The highest frequency heard by a listener at rest with respect to the centre of circle (velocity of sound in air $=330 \mathrm{~ms}^{-1}$ )

1 $590 \mathrm{~Hz}$
2 $594 \mathrm{~Hz}$
3 $598 \mathrm{~Hz}$
4 $602 \mathrm{~Hz}$
WAVES

173107 With what velocity should an observer approach stationary sound source so that the apparent frequency of sound appear to be double of the initial frequency?
(given velocity of sound $=v$ )

1 $\mathrm{v}_{0}=\mathrm{v} / 2$
2 $\mathrm{v}_{0}=3 \mathrm{v}$
3 $\mathrm{v}_{0}=2 \mathrm{v}$
4 $\mathrm{v}_{0}=\mathrm{v}$
WAVES

173108 An object producing a pitch of $400 \mathrm{~Hz}$ flies past a stationary person. The object was moving in a straight line with a velocity $200 \mathrm{~m} / \mathrm{s}$. The velocity of sound is $300 \mathrm{~m} / \mathrm{s}$. What is the change in frequency noted by the person as the object flies past him?

1 $1440 \mathrm{~Hz}$
2 $240 \mathrm{~Hz}$
3 $1200 \mathrm{~Hz}$
4 $960 \mathrm{~Hz}$
WAVES

173109 The frequency of a radar is $780 \mathrm{MHz}$. The frequency of reflected wave from aeroplane is increased by $2.6 \mathrm{kHz}$. Velocity of the aeroplane is

1 $0.25 \mathrm{~km} / \mathrm{sec}$
2 $0.5 \mathrm{~km} / \mathrm{sec}$
3 $1.0 \mathrm{~km} / \mathrm{sec}$
4 $2 \mathrm{~km} / \mathrm{sec}$
WAVES

173110 A whistle of frequency $540 \mathrm{~Hz}$ rotates in a horizontal circle of radius $2 \mathrm{~m}$ at an angular speed of $15 \mathrm{rad} / \mathrm{s}$. The highest frequency heard by a listener at rest with respect to the centre of circle (velocity of sound in air $=330 \mathrm{~ms}^{-1}$ )

1 $590 \mathrm{~Hz}$
2 $594 \mathrm{~Hz}$
3 $598 \mathrm{~Hz}$
4 $602 \mathrm{~Hz}$
WAVES

173107 With what velocity should an observer approach stationary sound source so that the apparent frequency of sound appear to be double of the initial frequency?
(given velocity of sound $=v$ )

1 $\mathrm{v}_{0}=\mathrm{v} / 2$
2 $\mathrm{v}_{0}=3 \mathrm{v}$
3 $\mathrm{v}_{0}=2 \mathrm{v}$
4 $\mathrm{v}_{0}=\mathrm{v}$
WAVES

173108 An object producing a pitch of $400 \mathrm{~Hz}$ flies past a stationary person. The object was moving in a straight line with a velocity $200 \mathrm{~m} / \mathrm{s}$. The velocity of sound is $300 \mathrm{~m} / \mathrm{s}$. What is the change in frequency noted by the person as the object flies past him?

1 $1440 \mathrm{~Hz}$
2 $240 \mathrm{~Hz}$
3 $1200 \mathrm{~Hz}$
4 $960 \mathrm{~Hz}$
WAVES

173109 The frequency of a radar is $780 \mathrm{MHz}$. The frequency of reflected wave from aeroplane is increased by $2.6 \mathrm{kHz}$. Velocity of the aeroplane is

1 $0.25 \mathrm{~km} / \mathrm{sec}$
2 $0.5 \mathrm{~km} / \mathrm{sec}$
3 $1.0 \mathrm{~km} / \mathrm{sec}$
4 $2 \mathrm{~km} / \mathrm{sec}$
WAVES

173110 A whistle of frequency $540 \mathrm{~Hz}$ rotates in a horizontal circle of radius $2 \mathrm{~m}$ at an angular speed of $15 \mathrm{rad} / \mathrm{s}$. The highest frequency heard by a listener at rest with respect to the centre of circle (velocity of sound in air $=330 \mathrm{~ms}^{-1}$ )

1 $590 \mathrm{~Hz}$
2 $594 \mathrm{~Hz}$
3 $598 \mathrm{~Hz}$
4 $602 \mathrm{~Hz}$
NEET Test Series from KOTA - 10 Papers In MS WORD WhatsApp Here