JEE Main2002PhysicsMathematics in PhysicsActual
Two forces are such that the sum of their magnitudes is 18 ~N and their resultant is 12 ~N which is perpendicular to the smaller force. Then the magnitudes of the forces are
Options
- A12 ~N , 6 ~N
- B13 ~N , 5 ~N
- C10 ~N , 8 ~N
- D16 ~N , 2 ~N
Correct answer
B. 13 ~N , 5 ~N
Step-by-step solution
Use = P Q+P 90^ = P Q+P = Q+P =0 P =-Q R = P ^2+ Q ^2+2 PQ R = P ^2+ Q ^2-2 Q ^2 or R = P ^2- Q ^2 =12144=( P + Q )( P - Q ) or P - Q =144 / 18=8 P =13 ~N and Q =5 ~N