A coolie is walking up a staircase with a load on his head. Is he doing any work?（Please answer in detail.）
Answers
Answered by
1
No, He is not doing any work.
REASON => Work = F(vector) . s(vector)
W = F s cos¢
Now, because he is walking up a staircase, so angle between the force and displacement is 90°.
So, Work = F s cos90
W = F s (0)..............cos90° = 0
W = 0
Thus, Work = 0........●
If the staircase is slant than the work depends on the angle ¢.
BUT THE WORK DONE BY THE COOLIE TO PUT THE LOAD ON HIS HEAD IS ZERO (0).
BECAUSE, THE ANGLE BETWEEN FORCE AND DISPLACEMENT IS 90° THERE.
SO, TOTAL WORK DONE BY HIM IS ZERO (0).
●●●●●●●●●●●●●●●●
Hope it was helpful.
REASON => Work = F(vector) . s(vector)
W = F s cos¢
Now, because he is walking up a staircase, so angle between the force and displacement is 90°.
So, Work = F s cos90
W = F s (0)..............cos90° = 0
W = 0
Thus, Work = 0........●
If the staircase is slant than the work depends on the angle ¢.
BUT THE WORK DONE BY THE COOLIE TO PUT THE LOAD ON HIS HEAD IS ZERO (0).
BECAUSE, THE ANGLE BETWEEN FORCE AND DISPLACEMENT IS 90° THERE.
SO, TOTAL WORK DONE BY HIM IS ZERO (0).
●●●●●●●●●●●●●●●●
Hope it was helpful.
leenaverma2009p8cmkg:
The angle between the force and displacement is not 90 degrees. It is a slant staircase. Work is done on a 'slant' scale.
I have edited the answer. You can see.. The work will be still 0.
Still not satisfied...
What is the confusion?
Where is the force and the displacement
The load is put on head froom the ground, thus it gets displacement upwards and the COOLIE applys some force for it, thus there is force. And because the angle between the surface and displacement is 90°. Thus work =:0 Simple.
Similar questions