A parachutist descends vertically a distance of 380 m at a constant speed of 2.9 m/s. The mass of the parachutist is 70 kg. What is the work done on the parachutist by the net force during this descent?
net force=mg*distance
To find the work done on the parachutist by the net force during the descent, we can use the formula:
Work = Force x Distance x Cosθ
Where:
- Work is the work done (in joules),
- Force is the net force acting on the parachutist (in newtons),
- Distance is the distance traveled by the parachutist (in meters), and
- θ is the angle between the force vector and the displacement vector (which, in this case, is 0 degrees since the parachutist is descending vertically).
In this case, the parachutist is descending vertically, so the angle between the force and displacement vectors is 0 degrees. Therefore, the cosine of 0 degrees is 1, and we can simplify the formula to:
Work = Force x Distance
First, let's find the force acting on the parachutist. We can use Newton's second law of motion:
Force = Mass x Acceleration
The parachutist is descending at a constant speed, so the acceleration is zero. Therefore, the force acting on the parachutist is also zero (since Force = Mass x Acceleration).
Since the force is zero, the work done on the parachutist is also zero.