Answer:
We show added energy to a system as +Q or -W
Explanation:
The first law of thermodynamics states that, in an isolated system, energy can neither be created nor be destroyed;
Energy is added to the internal energy of a system as either work energy or heat energy as follows;
ΔU = Q - W
Therefore, when energy is added as heat energy to a system, we show the energy as positive Q (+Q), when energy is added to the system in the form of work, we show the energy as minus W (-W).
Answer:
448 meters
Explanation:
every second it moves 8 meters, so all you have to do is multiply 56x8 or 8x56 either way it is the same thing and you will get the same answer
Answer: b) The velocity vector is perpendicular to the acceleration vector; the acceleration vector is parallel to the net force vector.
Explanation: A change in velocity creates an acceleration. As the object rotates through the circular path it is constantly changing direction, and hence accelerating, which causes a constant force to act upon the object. This Force acts towards the center of curvature, directly toward the axis of rotation in a direction parallel to the acceleration of the body along the path. Because the object is moving perpendicular to the force, the path followed by the object is a circular one. Hence the velocity of the object is perpendicular to the acceleration.
This is where we have to admit that gravitational potential energy is
one of those things that depends on the "frame of reference", or
'relative to what?'.
Potential energy = (mass) x (gravity) x (<em>height</em>).
So you have to specify <em><u>height above what</u></em> .
-- With respect to the ground, the ball has zero potential energy.
(If you let go of it, it will gain zero kinetic energy as it falls to
the ground.)
-- With respect to the floor in your basement, the potential energy is
(3) x (9.8) x (3 meters) = 88.2 joules.
(If you let go of it, it will gain 88.2 joules of kinetic energy as it falls
to the floor of your basement.)
-- With respect to the top of that 10-meter hill over there, the potential
energy is
(3) x (9.8) x (-10) = -294 joules
(Its potential energy is negative. After you let go of it, you have to give it
294 joules of energy that it doesn't have now, in order to lift it to the top of
the hill <em>where it will have zero</em> potential energy.)
Answer:
circuito paralelo
Explanation:
Siempre el circuito en paralelo dara una resistencia menor. Recuerda que las resistencias se suman en el circuito en serie, an cambio en el circuito en paralelo, la corriente se bifurca de manera de circular con mayor intensidad por las ramas que tengan menos resistencia, y tal situacion llevara siempre a producir una menor resistencia equivalente.
