Answer:
ΔS=2*m*Cp*ln((T1+T2)/(2*(T1*T2)^1/2))
Explanation:
The concepts and formulas that I will use to solve this exercise are the integration and the change in the entropy of the universe. To calculate the final temperature of the water the expression for the equilibrium temperature will be used. Similarly, to find the change in entropy from cold to hot water, the equation of the change of entropy will be used. In the attached image is detailed the step by step of the resolution.
Answer: B. II and III only
Explanation:
Let’s begin by explianing what energy is: the ability of matter to produce work in the form of movement, light, heat, among others. In this sense, there are several types of energy, but we will talk especifically in this case about <u>kinetic energy</u> and <u>potential energy</u>.
<u>Kinetic energy </u>is the energy an object or body has due to its movement and depends on the mass and velocity of the object or body.
To understande it better: If an object is at rest, its velocity is null and it does not have kinetic energy, however, if the object is moving, then it has kinetic energy.
On the other hand, <u>Potential energy</u> is known as <em>“stored energy”</em> that has the potential to be converted into energy of motion (kinetic energy) or another type of energy (thermal energy, for example). In addition, this energy is related to the work done when a certain force moves an object or body from its natural resting state along a distance to a new position.
So, according to this, Kinetic energy can be transformed into potential energy and Potential energy can be transformed into kinetic energy or any other type of energy. Hence, options II and III are correct.
Answer:
Explanation:
- The expression for acceleration of the rolling body on an inclined plane is given as a = gsinФ/1 + k²/R²
- where Ф is the angle of inclination, R is the radius, k is the radius of gyration.
- The potential energy of the system is given as ; PE = mgh
- The potential energy will be constant for ring, cylinder, solid sphere, and hollow sphere.
- The total kinetic energy of the rolling body is ; KE = mv²/2 + Iw²/2
- Hence, the total kinetic energy of the ring, cylinder, solid sphere and hollow sphere will be constant.
2. The moment of inertia of the ring is given as ;
I = mR²
The moment of inertia of the ring is maximum and therefore reaches the bottom last.
Answer:
900J
Explanation:
w =f×s
60×15
=900J
thus the k.e of the body is 900j
