A stone of density 5.20 g / cm3
and volume 200 cm3
is completely submerged in a liquid of
density 1.20 g / cm3
.
What is the magnitude of the upthrust acting on the stone?
[gravitational field strength = 10.0 N / kg]
A) 6.40 N
B) 2.00 N
C) 10.4 N
D) 8.00 N
E) 2.40 N
Hi!
density = m/V
so m=1,20 * 200=240g
Fb=m * g=0,24 * 10=2,4N
Hope this helps!
Why did you choose the density of the liquid instead of the density of the stone when calculating?
It talks about magnitude of upthrust which is produced by the liquid
The upthrust is basically the weight of fluid displaced. The volume of fluid displaced comes from the volume that the object occupies when submerged completely or incompletely. While multiplying w density gives us the mass of fluid displaced. In all multiplying that w G gives us the weight.