A police car moving at 22 m/s, chases 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 observes any beats 

(1) 33 m/s

(2) 22 m/s

(3) Zero

(4) 11 m/s

(2) n1 = Frequency of the police car horn observer heard by motorcyclist

n2 = Frequency of the siren heard by motorcyclist.

v2 = Speed of motor cyclist

n1 = 330v33022×176;n2=330+v330×165

n1n2=0v=22 m/s.

Difficulty Level:

  • 18%
  • 64%
  • 15%
  • 5%