Parachutist jumping from plane Conservation of Energy

AI Thread Summary
The discussion centers on calculating the change in internal energy of a parachutist using the conservation of energy principle. The parachutist has a mass of 70 kg, jumps from a height of 2500 m, and lands with a speed of 5.00 m/s. Participants clarify that the initial speed of the airplane (100 km/h) is irrelevant for energy calculations since the focus is on vertical motion. The initial velocity of the parachutist is considered to be 0 km/h in terms of vertical descent, though he retains the horizontal speed of the plane upon jumping. The conversation emphasizes the importance of converting units and understanding the role of air resistance in the calculations.
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Homework Statement



A parachutist with mass m = 70 kg jumps from an airplane traveling at a speed v = 100 km/h at a height H = 2500 m and lands with a speed vf = 5.00 m/s. Use the “conservation of energy strategy” to calculate the change in internal energy of the system from just after the jump until just before landing. (1E6)

Homework Equations



PE+KE=PE[f]+KE[f]

The Attempt at a Solution



I'm thinking that where it talks about the airplane traveling at 100 km/h makes no difference in this problem. So the actual initial velocity would be vi=0km/h then I think I would calculate the velocity without Air Resistance and then factor in the difference of speed. Am I headed in the right direction.
 
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He will have speed 100 km/h initially. Don't forget to convert to m/s.
 
Why though? is the plane traveling downward?
 
Direction is not important in calculating energy. The parachutist will have a horizontal speed of 100 - same as the plane - when he first let's go.
 

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