In every scene of your story, your characters should want something. What they want can vary wildly and often contradicts what other characters want. This is a part of creating conflict and tension. Today however, we’re talking a little bit about actions and reactions. More specifically, we’re discussing how emotional arcs work in scenes.
With the exception of a few characters, most of your characters will have some form of emotional movement. As people, our emotions often change in response to external stimuli. Within the context of a scene, that means your characters should have emotional responses as their scene-level goals are blocked, both by obstacles and other characters.

Keep in mind that there’s not a clear cut spectrum of emotions. Rather, they work more or less like a color wheel: shifting and blending into each other almost imperceptibly. Fear can turn into anger just as easily as it can give way to affection. The change is a result of the stimuli from outside.
For example: Your standard ‘monster under the bed’ complaint from many children. Their goal is pretty simple: get rid of whatever is under their bed that’s scaring them. Mom or Dad’s goal is to get some sleep. How the parents handle the complaint often affects the kid’s emotional arc.
Mom or Dad could easily get upset, scoffing at the complaints and dismissing their child’s statements. Kid eventually gives up, fear giving way to hopelessness, or perhaps even anger as they feel unprotected and unloved. This is a good place to ask how that might impact the character arc—do they lose trust in their parents at this point?
Alternately, Mom or Dad takes a moment to check out the under the bed, reassuring the Kid. Based on the response, the kid’s goal is satisfied, and their emotions taper into love and happiness, leaving them (hopefully) with pleasant dreams. Mom and Dad however, now have to deal with the regret of an half-hour of lost sleep. How would that effect the next morning?
Because each action causes an emotional reaction, this gives you an opportunity to build your scenes off one another and helps tie your character arcs directly into scenes of your story.
As an exercise: Take a scene from your story and label it with the emotional changes your characters go through. What causes their emotions to change? How are they feeling at the end of the scene? Then, when you’re finished, look at the next scene. How does the end of the previous scene impact the next?