00:01
For this problem on the topic of fluid mechanics, we are told the gravitational force that is exerted on a solid object, as well as the scale reading when the object is submerged in the water.
00:12
We are asked to then find the density of this object.
00:16
So if we draw a diagram, we have the buoyant force b acting upwards, as well as the scale force t acting upwards, and the weight of the object acts vertically downwards in the opposite direction.
00:30
Now we know for the submerged object, which is at equilibrium, the sum of all the forces in our y direction must equal to zero.
00:41
So this implies that the buoyant force, which is positive, minus the weight fg plus the scale force t must equal to zero, which means that if we make the buoyant force the subject of the formula, b is equal.
01:03
To the weight minus the scale rating t.
01:11
And this is 5 newtons, we are given the weight minus the scale rating of 3 .5 newtons.
01:21
So hence we know the buoyant force is 1 .5 newtons.
01:28
Now the point force is the same as the weight of the water that is displaced.
01:33
And its volume is the same as the volume v of the object...