A force of (10 hat(i) - 3 hat(j) + 6hat(k)) newton acts on a body of mass 100 g and displaces it from (6hat(i) + 5hat(j) - 3hat(k)) metre to (10hat(i) - 2hat(j) + 7hat(k))m. The work done is:

A force of (10 hat(i) - 3 hat(j) + 6hat(k)) newton acts on a body of m

1.	A force of (10 hat(i) - 3 hat(j) + 6hat(k)) newton acts on a body of mass 100 g and displaces it from (6hat(i) + 5hat(j) - 3hat(k)) metre to (10hat(i) - 2hat(j) + 7hat(k))m. The work done is:
Answer» 21J 361J 121J 1000J Solution :Displacement, `VEC(S)=vec(r_(2))- vec(r_(1))=(10hati - 2hatj+7hatk)-(6hati+5hatj-3hatk)` `=4hati -7hatj + 10hatk` Now work done, W`=vec(F).vec(S)` `=40 + 21 + 60=121J`

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A force of (10 hat(i) - 3 hat(j) + 6hat(k)) newton acts on a body of mass 100 g and displaces it from (6hat(i) + 5hat(j) - 3hat(k)) metre to (10hat(i) - 2hat(j) + 7hat(k))m. The work done is:

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