A rectangular boat is 7 m wide and 7 m long. After a truck pulls onto the ferry, the boat ends up with a depth of 1 cm submerged under the water.

Question

What is the combined weight of the truck and the ferry? (Assume the density of water is 1000 kg/m3.)

Answer 1

The key to this is determining the total volume of water displaced by the boat.

First, calculate the volume with the equation:

V=l*w*d;

V is volume, l is length, w is width, and d is depth

V=7m*7m*0.01m=0.49m³

Then rearrange the density equation and solve for mass since we know the volume displaced.

Density=mass/volume

Mass=Density*volume

Mass=1000kg/m³*0.49m³=490kg

Therefore the combined weight of the ferry and truck is 490kg.