1
Question
A rigid body of mass m kg is lifted with uniform velocity by a man to a height of 1 m in 30 seconds. Another man lifts the same mass with uniform velocity to the same height in 60 seconds. The work done on the body against gravity by them are in the ratio
A rigid body of mass m kg is lifted with uniform velocity by a man to a height of 1 m in 30 seconds. Another man lifts the same mass with uniform velocity to the same height in 60 seconds. The work done on the body against gravity by them are in the ratio
Open in App
Solution
The correct option is B 1:1
As we know,
Work done depends on the displacement of the body and the component of external force acting in the direction of its displacement.
So in this case displacement is some for both the cases.
Work done by 1st man =−mgh=−mg(1)=−mg
(negative because work done against the force due to gravity)
Work done by 2nd man, =−mgh=−mg(1)=−mg
Work done by 1st manWork done by 2nd man=−mg−mg=11
As we know,
Work done depends on the displacement of the body and the component of external force acting in the direction of its displacement.
So in this case displacement is some for both the cases.
Work done by 1st man =−mgh=−mg(1)=−mg
(negative because work done against the force due to gravity)
Work done by 2nd man, =−mgh=−mg(1)=−mg
Work done by 1st manWork done by 2nd man=−mg−mg=11
Suggest Corrections
30
Similar questions
View More
Join BYJU'S Learning Program
Explore more
Join BYJU'S Learning Program
