JEE Main & Advanced
JEE Main Paper (Held on 12-4-2019 Morning)
question_answer
If the angle of intersection at a point where the two circles with radii 5 cm and 12 cm intersect is\[90{}^\circ ,\]then the length (in cm) of their common chord is: [JEE Main Held on 12-4-2019 Morning]
A)\[\frac{60}{13}\]
B)\[\frac{120}{13}\]
C)\[\frac{13}{2}\]
D)\[\frac{13}{5}\]
Correct Answer:
B
Solution :
Let length of common chord \[=2x\]\[\sqrt{25-{{x}^{2}}}+\sqrt{144-{{x}^{2}}}=13\]after solving \[x=\frac{12\times 5}{13}\] \[2x=\frac{120}{13}\]