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Weight and Terminal Velocity

The diagram below shows a person using a device called a jet pack. Water is forced downwards from the jet pack and produces an upward force on the person.

a.) State the condition necessary for the person to be able to remain stationary in mid-air?

Reply 1

DataVenia

Volunteer Team, Clearing and Applications Advisor

Original post by Plsanswer344

The question tells us that the jet pack "produces an upward force on the person". Are there any other forces acting upon the person? A downward force perhaps? In order to the person to "remain stationary in mid-air" (i.e. not to rise and not to fall), what does this tell us about the relationship between the upward force and the downward force?

The question might also expect you to discuss forces that act horizontally (given that the requirement is that the person "remain stationary"). So what does this tell us about any sideways forces (e.g. due to wind) on the person?