NEET PHYSICS, System of particle & Rotational Motion. AIPMT 2012.

15 Two persons of masses 55 kg and
65 kg respectively, are at the
opposite ends of a boat. The
length of the boat is 3 m and
weighs 100 kg. The 55 kg man
walks upto the 65 kg man and sits
with him. If the boat is in still
water the centre of mass of the
system shifts by [AIPMT 2012)
la)3 m (b)2.3 m (c) zero (d)0.75 m
16 ABC is an equilateral triangle with
O as its centre. F,, F, and F,
represent three forces acting
along the sides AB, BC and AC,
respectively. If the total torque
about 0 is zero, then the
magnitude of F, is
[AIPMT 2012]
2