For a free body diagram shown in the figure, the four forces are applied in the ' x ' and ' y ' directions. What additional force must be applied and at what angle with positive x -axis so that the net acceleration of body is zero?
(A)2N,45∘✓ Correct
(B)2N,135∘
(C)32N,30∘
(D)2N,45∘
Answer: (A)
Solution
For zero net acceleration, the sum of all forces must be zero. Let the additional force be F.
From the figure, the net force from the four given forces is:
Fnet=(5−6)i^+(7−8)j^=−i^−j^
For equilibrium:
F+(−i^−j^)=0⟹F=i^+j^
Magnitude:
∣F∣=12+12=2 N
Angle with positive x-axis:
θ=tan−1(11)=45∘
JEE Main · 2022 · 25 Jul 2022 · Shift 2 · Single correct option