1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

# If the earth were to suddenly contract to half its present size, without any change in its mass, the duration of the new day be

A
18 hours
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
30 hours
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
6 hours
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
112 hours
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

## The correct option is C 6 hoursGiven,r2=12r1m1=m2=m(say)T1=24hrBy the conservation of angular momentum,I1ω1=I2ω2. . . . . . . . .(1)Where, ω=2πT angular velocity of the earthI=25mr2 moment of inertia of earth.From equation (1),25mr21.2πT1=25mr22.2πT2r21.1T1=r22.1T2T2T1=(r2r1)2=(r1/2r1)2=14T2=T1.14T2=244hr=6hrThe correct option is C.

Suggest Corrections
0
Join BYJU'S Learning Program
Related Videos
Variation in g
PHYSICS
Watch in App
Join BYJU'S Learning Program