Most Important Selected Qs for JEE AdvancedPhysicsWaves and Sound
S _ 1 : If pressure of a gas is increased keeping the temperature constant the speed of sound wave in the gas increases. S _ 2 : In a travelling sinusoidal sound wave the phase difference between displacement wave and pressure wave is 2 . S ₃ : The apparent frequency is v₁ , when a source approaches a stationary observer with speed u and is v₂ when the observer approaches the same stationary source with the same spee
Options
- AT F T
- BF T T
- CF F T
- DF T F
Correct answer
B. F T T
Step-by-step solution
S _ 1 : When pressure is increase density also increases in same proportion S _ 2 : True aligned & S ₃: v₁= v v-u v & v₂= [ u+v v ] v aligned v₁-v₂=v [ v v-u - u+v v ]=v [ v^2-v^2+u^2 (v-u) v ]= u^2 v (v-u) v 0