Question

A supersonic jet is moving with a velocity twice that of sound, the angle of conical wave front produced by the jet will be

• A. ${120}^0$
• B. ${90}^0$
• C. ${60}^0$
• D. ${30}^0$

Answer 1

Answer: (C)

${60}^0$

$\sin \alpha =\frac{V_s}{V_o}$,

$V_s$ is the velcity of sound in air and $V_o$ is the velocity of object.

$\alpha$ is the half angle of the cone vertex.

$\sin \alpha =\frac{V_s}{V_o}=\frac{1}{2}$,

$\alpha =30degrees$

$\text{angle of cone}=60degrees$

Option 'C' is correct.