If three parachutist one-50kg, second-40 kg and thrid-75kg from fastest to slowest what is there total terminal velocities.Then from longest to shortest time rank their order in reaching the ground ?
If all three parachutists jump from the same height, they will all reach the ground at the same time and same speed, assuming air resistance is negligible. The parachutists’ masses have no effect on their speeds because on Earth, all objects accelerate at g when they are free-falling.
In response to the Gordon Zheng, ‘Terminal Velocity’ implies that air resistance is not negligible. (Though I see that this is a page-63, exercise 1 question… so maybe it is supposed to be taken as simply as you explained it.)
That being said, terminal velocity is dependent on both mass and area, as well as the drag coefficient/gravity constant (i.e. terminal velocity on earth vs. another planet would be different, all other things being equal).
In assuming that the parachutists have the same area, then, the terminal velocity of the greater mass will be correspondingly greater. The order from fastest to slowest would be: 75 kg, 50 kg, 40 kg.
The time to reach the ground would be the opposite (slower velocity = more time to cover the same distance).