posted by John on .
Can you please go over my answers to see if Im correct Im having trouble in this class.
A car with mass 2000kg is held at a height of 1.8 meters by a hydraulic lift. The surface area of the piston inside the lift is 300cm², and the surface area of the input tube at the bottom of the lift is 6 cm². What force must be exerted on the fluid in the input tube to hold the car up? (Neglect the mass of the fluid itself.)
Is the answer C
What is the pressure at the bottom of a tube of mercury that is 0.2 m deep?
I think the answer is B
Rank in order of weight: 5 cc of gold, 10cc of lead or 100cc of water.
A)20cc of silver is heaviest, 12 cc of platinum is next, and 100cc of aluminum is lightest.
B)100cc of aluminum is heaviest, 12 cc of platinum is next, and 20cc of silver is lightest.
C)12 cc of platinum is heaviest,100cc of aluminum is next, and 20cc of silver is lightest.
D)all three weigh the same
I think the answer is D
Sometimes when I get in my swimming pool I take a plastic cup filled with wine with me. The cup holds 400 cc of wine. I have observed that the cup sinks when it is full of wine, but floats after I have drunk at least 1/4 of it. What is the mass of the cup? Assume that the specific gravity of the wine is 1.04.
I think the answer is C
2000 *6/300 * 9.8 = 392 N so D(they probably called g = 10)
I do not have a table of densities handy, sorry