Question

a train moving with the speed of 72kmph towards a station is sounding a frequency of 600Hz. What are the apparent frequencies of the whistle as heard by a man on a platform when the train
1) approaches him
2)recedes from him
(speed of sound in air is 340m/s)

Answer 1

Answer:-

1) Source moving towards the observer

f' = [ ( v + b) / ( v - a) ] x f

v = 340 m/s

b = 0

a = 72 km/hr = 20 m/s

f = 600 Hz

f' = [ 340/ (340 -20)] x 600 = 637.5 Hz

2)  Source moving away from observer

f' = [ ( v - b) / ( v + a) ] x f

v = 340 m/s

b = 0

a = 72 km/hr = 20 m/s

f = 600 Hz

f' = [ 340/ (340 + 20)] x 600 = 566.7 Hz

Answer 2

Answer:

Hydrogen has the simplest electronic configuration of one. In group one it loses one electron and in group seventeen it gains one electron. The number of atoms of similar elements that combine to form a molecule. Hydrogen is diatomic in Nature.