MCQ
Doppler's effect will not be applicable when the velocity of sound source is
- AEqual to that of the sound velocity
- BLess than the velocity of sound
- ✓Greater than the velocity of sound
- DZero
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[Use $hc =1242 eV nm ; 1 nm =10^{-9} m , h$ and $c$ are Planck's constant and speed of light, respectively]
$(1)$ $\lambda_0=418 nm$
$(2)$ The ratio of kinetic energy of the electron in the state $n = m$ to the state $n =1$ is $\frac{1}{4}$
$(3)$ $m =2$
$(4)$ $\Delta p_{ a } / \Delta p _{ o }=\frac{1}{2}$