Start Free Mock LoginAlready registered? Login here

Physics - Rotation Question with Solution | TestHub

PhysicsRotationAngular momentumMedium2 minQB

PhysicsMediumnumerical

If the radius of earth is reduced to three-fourth of its present value without change in its mass then value of duration of the day of earth will be $____$ hours 30 minutes. Assume duration of present day is exactly 24 hrs.

Answer:

13.00

Solution:

By conservation of angular momentum

$I_{1} ω_{1} = I_{2} ω_{2}$

$(\frac{2}{5} M R^{2}) \frac{2 π}{T _{1}} = \frac{2}{5} M (\frac{3}{4} R)^{2} \frac{2 π}{T _{2}}$

$\frac{1}{T _{1}} = \frac{9}{16 T _{2}}$

$T_{2} = \frac{9}{16} \times T_{1} = \frac{9}{16} \times 24 hr = \frac{27}{2} hr = 13 hr 30 mins.$

Stream:JEESubject:PhysicsTopic:RotationSubtopic:Angular momentum

⏱ 2mℹ️ Source: QB

Doubts & Discussion

Loading discussions...