Suppose that the speed of sound in air at a given temperature is 400 m/sec. An engine blows a whistle at 1200 Hz frequency. It is approaching an observer at the speed of 100 m/sec. What is the apparent frequency as heard by the observer [CPMT 1983; DPMT 2001]

If assertion is true but reason is false.

Suppose that the speed of sound in air at a given temperature is 400

1.	Suppose that the speed of sound in air at a given temperature is 400 m/sec. An engine blows a whistle at 1200 Hz frequency. It is approaching an observer at the speed of 100 m/sec. What is the apparent frequency as heard by the observer [CPMT 1983; DPMT 2001]
A.	600 Hz
B.	1200 Hz
C.	If assertion is true but reason is false.
D.	1600 Hz
Answer» E.

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Suppose that the speed of sound in air at a given temperature is 400 m/sec. An engine blows a whistle at 1200 Hz frequency. It is approaching an observer at the speed of 100 m/sec. What is the apparent frequency as heard by the observer [CPMT 1983; DPMT 2001]

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