A body of mass m at rest explodes into 3 partrs, having masses in ratio 1:1:3. If two parts having equal masses move at right angles to each other with 10 m/s each , the velocity of third will be

Question

$$(a)\;\sqrt 2 \;m/s \quad (b)\;5 \sqrt 2\;m/s \quad (c)\;5\;m/s \quad (d)\;10 \sqrt 2\;m/s$$