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

A body of mass m was slowly hauled up the hill as shown in fig. by a force F which at each point was directed along a tangent to the trajectory. Find the work performed by this force, if the height of the hill is h, the length of its base is l and the coefficient of friction k
1215056_23de1286725149eea9887c62a8cacfb6.png

A
mg h
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
mg (h+kl)
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
mg (hkl)
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
None of these
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is A mg h
Applying work energy theorem
Change in kinetic energy=work done by all forces
=Wmg+Wext
work by gravity=mgh (ve sign is because work is done against gravity)
Work by F is Wext
Change in kinetic energy=0
so,
Wextmgh=0
Wext=mgh
So work by force F is mgh, this work will not depend on the angle of incline...

flag
Suggest Corrections
thumbs-up
1
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Falling Balls in Disguise
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon