Answer:
(1) A hot drink cooling to room temperature.
(2) The combustion of natural gas.
Explanation:
The spontaneous process is the process in which there is a release of energy and moves towards lower energy and a more thermodynamically stable energy state. All the natural processes are spontaneous.
There are two processes which are spontaneous in the given question are:
(1) A hot drink cooling to room temperature: In this, there is a decrease in energy and also it is a natural process and we know that all the natural processes are spontaneous.
(2) The combustion of natural gas: The fire is an example of an exothermic reaction. The combustion is a combination of a decrease in energy and an increase in entropy. So, this process occurs spontaneously.
Answer: 7.41 m/s
Explanation: By using the law of of energy, kinetic energy of the brick as it falls equals the potential energy before falling.
Kinetic energy = mv²/2, potential energy = mgh
mv²/2 = mgh
v²/2 = gh
v² = 2gh
v = √2gh
Where g = 9.8 m/s², h = 2.80m
v = √2×9.8×2.8 = 7.41 m/s
Answer:D) His Facial expressions when they spend time together
Explanation:
Eva's should carefully observe the normal verbal signs by her lover because facial expression gives the hint to listener or viewer that one is interested towards other.
Some common facial Expression are
- Smiling Eyes:While smiling is, of course, an important expression when we speak, attempting to keep a constant smile could make you look more like a trained sociopath than a happy, enthusiastic presenter. These enables other person to feel the good vibes out of you and left a positive impact of your presence.
- Nod on: It is important to express interest in the feedback of your audience. No one likes an identity-centered snob. One way to show that you're actually engaged in the comments and questions they pose is by nodding while you're listening. Moving your head a little wider will help to express your attention as well.
You can describe the motion of an object by its position, speed, direction, and acceleration