Homework Help: Physics

Posted by Randi on Friday, January 29, 2010 at 2:48pm.

Hey guys - this problem is pretty tough for me...any help? Don't know what to do....
In seawater, a life preserver with a volume of 4.00×10^−2 m^3 will support a 76.0 kg person (average density 980 kg/m^3), with 20.0 % of the person's volume above water when the life preserver is fully submerged. What is the density of the material composing the life preserver? (answer in kg/m^3)
Thanks!

Physics - bobpursley, Friday, January 29, 2010 at 3:25pm
weight displaced salt water= bouyancy force

Volume displace*densityseawater*g=bouyant force
(4E-2m^3*density*g+.8*76/980*g)= 76g+
4*E-2*density*g

check that and solve for density. Notice the g factor divides out.

Answer this Question

Related Questions

physics - hey you guys , i reay appreciate it if you guys help me out . Q: a ...
physics - A block of wood will sink 10 cm in freshwater. How far will it sink in...
College Chemistry - So i been trying to solve this question like for ever! so i ...
English - Hey guys, I was just wondering if you could help me find or explain ...
Physics - Seawater has a bulk modulus of 2.34×109 N/m2. Its density at 5&...
Physics - A block of wood will sink 10 cm in freshwater. How far will it sink in...
Physics - Can you please show all your work so that I can understand how the ...
Physical Chemistry - The measured osmotic pressure of seawater is 25 atm at 273K...
PLEASE HELP! PHYSICAL CHEM - The measured osmotic pressure of seawater is 25 atm...
chemistry hw - SOMEONE PLEASE HELP AND CONFIRM THE RIGHT ANSWER FOR ME...I HAVE ...

For Further Reading

First Name:
School Subject:
Answer: