Question

Gravitational field in a region is given by $( 3 \hat { i } + 2 \hat { j } )$ N kg^-1. Find the work done by the gravitational field when a particle of mass m moves from one point (x₁, y₁)to another (x₂, y₂) on the line 2y + 3y = 6

• A. Zero
• B. 9(x₂ – x₁) + 4(y₂ – y₁)
• C. 9(x₁ – x₂) + 4(y₁ – y₂)
• D. None

Answer 1

Answer: (A)

Zero

Answer 2

m₁(slope of the line) = $\frac { - 3 } { 2 }$

Slope of gravitational field m₂ =

m₁m₂ = - 1 i.e. line and field are perpendicular.

Hence, work done = 0