NEET-XI-Physics
exam-2 year:2016
- #119A particle moves from a point ``(-2\hat{i} + 5\hat{j})`` to
+ ``(4\hat{j} + 3\hat{k})`` when a force of ``(4\hat{i} + 3\hat{j})`` N is applied.
How much work has been done by the force ?
(1) 5 J
(2) 2 J
(3) 8 J
(4) 11 JdigAnsr: 1Ans : (1)
Sol. f i ˆˆ ˆs r r 2i j 3k= = +
ˆˆ ˆ ˆW F.s 4i 3j . 2i j 3k 8 3 5J = = + + = =