# B Resultant Force of a skydiver

When a skydiver falls at terminal velocity, and opens his parachute, what will be the direction of the resultant force immediately after he opens his parachute?
As far as I know is that the direction of acceleration will be upwards since his velocity is decreasing. I am a bit confused regarding the direction of resultant force.
Thanks.
(REGARDS)

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#### Drakkith

Staff Emeritus
2018 Award
As far as I know is that the direction of acceleration will be upwards since his velocity is decreasing. I am a bit confused regarding the direction of resultant force.
If the acceleration is upwards, and acceleration requires a force, then what is the direction of the force?

If the acceleration is upwards, and acceleration requires a force, then what is the direction of the force?
Upwards?

#### Drakkith

Staff Emeritus
2018 Award
That's right. If there is a net force to the side or downwards instead, what would happen to the skydiver?

That's right. If there is a net force to the side or downwards instead, what would happen to the skydiver?
The skydiver will fall down at an increasing velocity? (Because the acceleration will be downwards)

#### Drakkith

Staff Emeritus
2018 Award
Yep. If the skydiver is at terminal velocity, then the resultant forces are zero and they are not accelerating. Upon opening their parachute, the upward force from the air greatly increases, causing them to decelerate. As their airspeed decreases, the upward force decreases as well, until it is balanced with gravity again.

Last edited:

Yep. If the skydiver is at terminal velocity, then the resultant forces are zero and they are not acceleration. Upon opening their parachute, the upward force from the air greatly increases, causing them to deceleration. As their airspeed decreases, the upward force decreases as well, until it is balanced with gravity again.
Well, this was the best explanation. Thanks a lot for making things clear :)

"Resultant Force of a skydiver"

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