wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

A man m=80 kg is standing on a trolley of mass 320 kg on a smooth surface. If man starts walking on trolley along rails at a speed of 1 m/s, then after 4 sec, his displacement relative to ground is

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

The correct option is C 3.2 m
v=1m/s is velocity relative the trolley so if trolley is moving at V opposite to the man
then velocity of man in ground frame will be vV

Note- As initially the trolley and man were at rest. so the velocity of center of mass should be zero all the time until
applied by some external force.
so we should get 0=80(vV)+320×(V)80+320 (negative V because towards left.)

from the formula Vcm=m1(V1)+m2×(V2)m1+m2

putting v=1 and on solving we get V=0.2m/s towardsleft.$
Displacement of man relative to ground will be time×(vV)=4×0.8=3.2meter

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Friction in Rolling
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon