What is the object of prepositional phrase with such force?

You're asking about the object of the prepositional phrase "with such force." To answer this, let's break it down:

* Prepositional phrase: "with such force"

* Preposition: "with"

* Object of the preposition: "such force"

Therefore, the object of the prepositional phrase "with such force" is "such force."

Example:

"The ball was thrown with such force that it shattered the window."

In this example, "with such force" modifies the verb "thrown" and tells us how the ball was thrown. The object of the preposition "with" is "such force," which describes the intensity of the throw.