A boy carrying a bag on his shoulders walking at an angle of 90 degrees.
We need to check if the work id done.
We know that the work done is calculated by
W=Fx S x Cosx,
The displacement here is zero hence no work is done. And also according to work-energy theorem work done is equal to change in kinetic energy. No change in kinetic energy is observed. So work done is zero. We know that,
Work Done = F×s×cosx
Hence A boy carrying a bag on his shoulders walking at an angle of 90 degrees we can tell that no work is done.