Saved Bookmarks
| 1. |
When two forces of magnitude P and Q are perpendicular to each other, their resultant is of magnitude R. When they are at an angle of `180^(@)` to each other, their resultant is of magnitude `(R )/(sqrt2)`. Find the ratio of P and Q.A. `sqrt3 +- 2`B. `2 +- sqrt3`C. `3 +- sqrt5`D. `5 +- sqrt3` |
|
Answer» Correct Answer - B `P^(2) + Q^(2) = R^(2)` ….(i) `|P - Q| = (R )/(sqrt2)` ….(ii) Squaring (2). `P^(2) + Q^(2) - 2PQ = (R^(2))/(2)` …..(iii) from (1) & (3) `2PQ = (R^(2))/(2)` `P^(2) + Q^(2) = R^(2) = 4PQ` `P^(2) - 4PQ + Q^(2) = 0` `(P^(2))/(Q^(2)) - (4P)/(Q) + 1 = 0` `(P)/(Q) = (4 +- 2 sqrt3)/(2) = 2 +- sqrt3` |
|