A shell at rest at the origin explodes into three fragments of masses 1 kg , 2 kg and M kg. the 1 kg and 2 kg pieces fly off ….

Q: A shell at rest at the origin explodes into three fragments of masses 1 kg , 2 kg and M kg . The 1 kg and 2 kg pieces fly off with speeds of 5 m/s along x-axis and 6 m/s along y-axis respectively. If the m kg piece files off with a speed of 6.5 m/s, the total mass of the shell must be

(a) 4 kg

(b) 5 kg

(c) 3.5 kg

(d) 4.5 kg

Ans: (b)