Answer:
Choice A: approximately
, assuming that the two pistons are connected via some confined liquid to form a simple machine.
Explanation:
Assume that the two pistons are connected via some liquid that is confined. Pressure from the first piston:
.
By Pascal's Principle, because the first piston exerted a pressure of
on the liquid, the liquid will now exert the same amount of pressure on the walls of the container.
Assume that the second piston is part of that wall. The pressure on the second piston will also be
. In other words:
.
To achieve a force of
, the surface area of the second piston should be:
.
Answer:
P = 4.5 watts
Explanation:
Given that,
EMF of the circuit, E = 3 volt
The resistance of the resistors, R = 2 ohms
We need to find the power of this circuit. The relation between power, emf and resistance is given by the formula as follows :

Substitute all the values,

So, the power of this circuit is equal to 4.5 watts.
Density =mass/Volume
0.8=mass/60
Mass=0.8*60
Mass=48g