Question
A uniform force of (3 i + j) N acts on a particle of mass 2 kg. Hence the particle is displaced from position (2 i + k) m to position ( 4 i + 3 j - k) m. The work done by the force on the particle is,
-
9 J
-
6 J
-
13 J
-
15 J
Solution
A.
9 J
Given,
Force, F = 3 i + j
r1 = ( 2 i + k) m
r2 = (4 i + 3 j - k) m
Therefore,
S = r2 - r1
Therefore,
W = F. s
= (3i + j). (2 i +3j - 2k)
= 3 x2 + 3x0
= 6 + 3 = 9 J
