Question

the force of 2i+5j displaced a body from (2,1,1) to ( 1,2,3) find work done​

Answer 1

Answer:

W.D. = F . r

r = [2–1]i + [1–2]j +[1–3]k = 1i -1j -2k

F.r = [ 2i+5j+ok].[1i -1j -2k] = [2][1] +[5][-1] +[0][-2] = -3

|F.r| =3