Question

A square wooden raft floats on a lake. The density of the water in the lake is 1000 kg/m². The sides of the raft are 2.0m long and the thickness of the raft is 0.20 m. The mass of the raft is 700 kg. How many barrels, each of mass 100 kg, could be placed on the raft before its surface sinks to the surface of the water?​

Answer 1

Answer:

1

Explanation:

V=2*2*0.2=0.8m^3

d=m/v 1000*0.8=800kg

800=700+100(n)            (n for barrels)

n=1

Answer 2

This question deals with the concept of buoyancy. This can be solved by calculating the buoyant force.

"1" barrels, each of mass 100 kg, could be placed on the raft before it sinks to the surface water.

First, we need to calculate the buoyant force on the raft due to water. This force is equal to the weight of the volume of water equal to the volume of the raft.

Buoyant Force = (Volume of Raft)(Density of Water)(g)

Buoyant Force = [(2 m)(2 m)(0.2 m)][1000 kg/m³](9.81 m/s²)

Buoyant Force = (0.8 m³)(1000 kg/m³)(9.81 m/s²)

Buoyant Force = 7848 N

For the raft to sink the weight of the raft combined with the weight of barrels must exceed the buoyant force. Now, we will calculate the weight of raft and barrels and equate it with the buoyant force.

[Mass of Raft + (No. of Barrels)(Mass of 1 Barrel)][g] = Buoyant Force

[700 kg + (No. of Barrels)(100 kg)][9.81 m/s²] = 7848 N

(No. of Barrels)(981 N) = 7848 N - 6867 N

$No. of Barrels = \frac{981\ N}{981\ N}$

No. of Barrels = 1

The attached picture shows the concept of buoyancy.

Learn more about buoyancy here:

https://brainly.com/question/21990136?referrer=searchResults