A raft of wood of mass 120 kg float. in water. The weight that can be put on the raft to make it just sink, should be (draft=600kg/m3):

Question

A raft of wood of mass 120 kg float. in water. The weight that can be put on the raft to make it just sink, should be (draft=600kg/m3):  (A) 80 kg (B) 50 kg (C) 60 kg (D) 30 kg

Tardigrade Admin · Accepted Answer

Volume of raft is given by V=(m/d)=(120/600)=0.2 m3 If the raft is immersed fully in water, Then weight of water displaced is =Vdwater =0.2× 103=200 kg Hence, the additional weight which can be put on the raft =200kg-120kg=80kg

Q. A raft of wood of mass 120 kg float. in water. The weight that can be put on the raft to make it just sink, should be $(d_{r a f t} = 600 k g / m^{3}) :$

80 kg

50 kg

60 kg

30 kg

Volume of raft is given by $V = \frac{m}{d} = \frac{120}{600} = 0.2 m^{3}$ If the raft is immersed fully in water, Then weight of water displaced is $= V d_{w a t er}$ $= 0.2 \times 10^{3} = 200 k g$ Hence, the additional weight which can be put on the raft $= 200 k g - 120 k g = 80 k g$

Q. A raft of wood of mass 120 kg float. in water. The weight that can be put on the raft to make it just sink, should be (draft​=600kg/m3):