-- If the system is 'closed', then nothing ... including energy ... can get in or out, and the total energy inside has to be constant.
If half of the energy in the system starts out as potential energy and the rest starts out as kinetic, and then the potential energy increases, there's only one place the increase could have come from ... it could only have been converted from kinetic energy. So the <em>kinetic energy</em> in the system <em>must</em> <em>decrease</em>.
In fact, this isn't even a "result". The kinetic energy has to decrease <em><u>before</u></em> the potential energy can increase, because that's where the increase has to come from.
If the system is 'open', then energy can come in and go out. If the potential energy inside suddenly increases, we don't know where it came from, so we can't say anything about what happens to the system.
Explanation:
For the equilibrium:
\rho_{wood}gh-\rho_{oil}g(h-x)-\rho_{water}gx=0ρ
wood
gh−ρ
oil
g(h−x)−ρ
water
gx=0
\rho_{wood}h-\rho_{oil}(h-x)-\rho_{water}x=0ρ
wood
h−ρ
oil
(h−x)−ρ
water
x=0
(974)(3.97)-928(3.97-x)-1000x=0(974)(3.97)−928(3.97−x)−1000x=0
x=2.54\ cmx=2.54 cm
The momentum p of a moving particle is the product between its mass, m, and tis velocity, v:
In our problem, we know
and
, and using the relationship mentioned above, we can find the mass m of the particle:
A
Cl is the chemical symbol for chlorine numbers after it are isotopes
