Question

A body, constrained to move in the Y-direction is subjected to a force given by $\vec { F } = ( - 2 \hat { i } + 15 \hat { j } + 6 \hat { k } ) N$ What is the work done by this force in moving the body a distance 10 m along the Y-axis

• A. 20 J
• B. 150 J
• C. 160 J
• D. 190 J

Answer 1

Answer: (B)

150 J

Answer 2

$W = \vec { F } \cdot \vec { r }$ $= ( - 2 \hat { i } + 15 \hat { j } + 6 \hat { k } ) ( 10 \hat { j } ) = 150$