Question

A force of $( 3 \hat { i } + 4 \hat { j } )$ Newton acts on a body and displaces it by $( 3 \hat { i } + 4 \hat { j } ) m$ The work done by the force is

• A. 10 J
• B. 12 J
• C. 16 J
• D. 25 J

Answer 1

Answer: (D)

25 J

Answer 2

$W = \vec { F } \cdot \vec { s }$ $= ( 3 \hat { i } + 4 \hat { j } ) \cdot ( 3 \hat { i } + 4 \hat { j } ) = 9 + 16 = 25 J$