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.Question 3: Neglecting air resistance, what is the total velocity of a parachutist just before engaging his parachute, 8 s after dropping from an airplane flying horizontally at 60 m/s?
\80 m/s? 140 m/s? 100 m/s? or 60 m/s?
\\
Step 1:
\Parachutist is freely jumping from the plane, so he is treated as a freely falling body.
\Vertical downward force :
\Freely falling bodies have a downward velocity is .
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is acceleration due to gravity (10 m/s2 ),
t is time.
\Velocity after 8 second is
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Airplane flying horizontally at speed of 60 m/s.
\Step 2:
\Find the resultant total velocity.
\Resultant velocity is the vector sum of horizontal and vertical velocities of parachutist.
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Therefore the resultant velocity is 100 m/s.
\Option (c) is correct choice.
\Solution :
\Option (c) is correct choice.