First of all, concerning Orwell's "Shooting an Elephant," Orwell presents powerful ideas--that the English should get out of Burma as quickly as possible, and that the English, by subjecting others to their will, actually lose their own freedom--and powerful ideas usually evoke powerful emotions in those that receive the ideas--in this case, readers. Orwell, or his speaker, is decidedly against imperialism in this essay, and he does seek to evoke strong emotions in the reader in order to inform and persuade.
He presents his ideas in numerous ways, far too many to cover thoroughly here. But I'll explain a few for you.
Let's look at the actual killing of the elephant. Emotion is evoked in this scene by the use of precise and insightful description. Orwell writes:
In that instant, in too short a time, one would have thought, even for the bullet to get there, a mysterious, terrible change had come over the elephant. He neither stirred nor fell, but every line on his body had altered. He looked suddenly stricken, shrunken, immensely old, as though the frightful impact of the bullet had paralyzed him without knocking him down. At last, after what seemed a long time--it might have been five seconds, I dare say--he sagged flabbily to his knees.
Look at the diction, or word choice, and the phrasing:
- mysterious, terrible change
- stricken, shrunken, immensely old
- frightful impact
- paralyzed, without knocking him down
- sagged flabbily to his knees
And notice the image created by "paralyzed him without knocking him down." The description, diction, phrasing, imagery all present concrete details that evoke powerful emotion in the reader.
And the elephant scene is, of course, central to Orwell's ideas. He is an outsider forced to do what he doesn't want to do by the crowd of insiders surrounding him, and his action is loaded with ambiguity concerning its consequences.
Orwell tries to evoke pity, disgust, righteous indignation. He wants readers to decide that imperialism destroys both the colonizers and the colonized.
In my opinion, Orwell is trying to provoke a number of emotions -- different ones at different points.
At the beginning of the essay, it seems that Orwell is trying to make us dislike the Burmese. I think he is doing that so we will understand how colonialism degrades people. He makes us dislike them by showing how they mistreat white women. Because we still feel protective towards women, it seems very wrong to abuse them. And it seems especially wrong to spit on them. By describing this, Orwell makes us dislike the Burmese.
I'll give one more example:
Later on, Orwell wants us to pity the elephant so that we understand how much he dislikes what he is being forced to do. He does this by describing elephants as "grandmotherly." And then he does it by describing how the elephant seems after it gets shot.