Question

find the work done in moving an object along a vector 4i+5k if an applied force is -3i+2k is
A) 2
B) -2
C) 22
D) -22​

Answer 1

Answer:

B) - 2

Explanation:

$w = f.s \\ = ( - 3i + 2k).(4i + 5k) \\ = - 12 + 10 \\ = - 2$

Answer 2

Answer:-2

Explanation:

W=F.D

As per dot product

i.i=kk=0

There fore

W=(4)(-3)+(5)(2)

W=-12+10

W= -2 Ans