# Help with physics of hoover dam

1. Mar 23, 2005

### pete22

i have a problem where i have to find out how mych force the hoover dam has on it. i have to take into account the force the water is putting on the dam and the gravitational force that is being created by the actual wall taking into account the mass of the wall. help i dont know where to start.

2. Mar 23, 2005

have you done fluid mechanics yet?

Regards,

3. Mar 23, 2005

### marlon

Use Pascall's principle and the fact that p =p_0 + g*h*j where p_0 is the atmospheric pressure and j is the mass-density of water.

regards
marlon

4. Mar 23, 2005

### PRodQuanta

Like marlon said, use the equation:
$$P=P_0 + \rho gh$$
where: $$\rho$$ = density of water $$= 1.00x10^3 kg/m^3$$
and $$P_0$$ = $$1.01x10^15 Pa$$

When you find $$P$$, then you use the equation for $$P$$ (pressure): $$P = F/A$$ to solve for $$F$$
($$A$$ = the area of water in contact with the dam.)

Once you have this, you have the Force that the water exerts on the dam (make sure you find both Force vectors. One side will have a large vector, where the other side, while still having a vector, will be very small)

Your next step will be finding the weight of the dam itself. Use the formula
$$w=mg$$ where $$w$$ is weight.

Add these up and "Eureka! You've found it!"
(Pardon the pun)