help with buoyancy question thanks!!

jlin94

An object denser than water rests on the bot-
tom of a container full of water. The object
has volume V and a density p = 4 pw, where
pw is the density of water.

What supporting force N does the con-
tainer bottom exert on the object, in terms of
pw, g and V ?


2. Relevant equations
Normal force= force pressure + weight


3. The attempt at a solution
N = F + mg
N = PxA + pVg
N= ....+ 4 pwVg

i dont know how to finish this?
could some explain what to do now to solve for Force normal

thanks!

technician

If the object is on the bottom of the container then there is definetly an upwards force on the object by the bottom of the container. There is also another force due to buoyancy.... do you know how to calculate this 'upthrust'?
Both forces together must equal the weight of the object.
Can you take it from there?