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A 65kg skydiver opens her parachute. Air resistance to her body is 20 N and the lift force is 617N. What is the net force acting on her. (Create a free body diagram)

User Demian Sims
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1 Answer

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18 votes

Free body diagram:

When the skydiver opens her parachute, the lift force (617 N) and air resistance (20 N) act in the upward direction and the weight (mg) acts downwards (towards the center of the earth).

The net force acting on the skydiver is given as,


\begin{gathered} F_(net)=\text{Lift}+\text{ Air resistance}-\text{ Weight} \\ =\text{Lift}+\text{ Air resistance}-mg \end{gathered}

Here, m is the mass of the skydiver (65 kg) and g is the acceleration due to the earth's gravity (9.8 m/s²).

Substituting all known values,


\begin{gathered} F_(net)=(617\text{ N})+(20\text{ N})-(65\text{ kg})*(9.8\text{ m/s}^2) \\ =0\text{ N} \end{gathered}

Therefore, no net force (0N) acting on the skydiver.

A 65kg skydiver opens her parachute. Air resistance to her body is 20 N and the lift-example-1
User Gbjbaanb
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