Definitions of suspense

Suspense is a feeling of uncertainty and anxiety about the outcome of certain actions, most often referring to an audience's perceptions in a dramatic work. Suspense is not exclusive to fiction, though. Suspense may operate in any situation where there is a lead up to a big event or dramatic moment, with tension being a primary emotion felt as part of the situation. In the kind of suspense described by film director Alfred Hitchcock, an audience experiences suspense when they expect something bad to happen and have (or believe they have) a superior perspective on events in the drama's hierarchy of knowledge, yet they are powerless to intervene to prevent it from happening. In broader definitions of suspense, this emotion arises when someone is aware of his lack of knowledge about the development of a meaningful event; thus, suspense is a combination of anticipation and uncertainty dealing with the obscurity of the future. In terms of narrative expectations, it may be contrasted with mystery or curiosity and surprise. Suspense could however be some small event in a person's life, such as a child anticipating an answer to a request they've made, e.g., "May I get the kitty?". Therefore, suspense comes in many different sizes, big and small.

Suspense in Jaws:-

There are microfeatures which create the suspense in this scene which are: mise en scene, sound, camera and editing.

In Jaws people are having fun on the beach, people are laughing. This makes the audience feel reassured and relaxed. Then we hear the music beginning coming in which is kind of classical. People are splashing around in the water.
We then see the camera go under the water which is like the point of view of a shark.
The editing begins to pick up the pace when they think that a shark is in the water, this creates a sense of panic. People are rushing out of the water.
But then we realise that it is just a hoax played by kids pretending to be a shark with a cardboard fin.

Suddenly a woman screams out "shark", then the music starts to pick up speed, which shocks the viewers. The shark then attacks the man and the viewers see the camera follow a leg torn off sinking in the water.