I need help with number 20 19. Determine the power developed by a manweighing 6.0 × 10² newtons who climbs a ropeat a constant speed of 2.0 meters per second.20. Student A lifts a 40.-newton box from the floorto a height of 0.30 meter in 2.0 seconds. StudentB lifts a 30.-newton box from the floor to aheight of 0.40 meter in 4.0 seconds. Comparedto student A, student B does(1) less work but develops more power(2) more work but develops less power(3) the same work but develops less power(4) the same work but develops more power21. A 5.0 × 10²-newton girl develops 250 watts ofpower as she runs up two flights of stairs to alanding a total of 5.0 meters vertically above herstarting point. Calculate the time required forthe girl to run up the stairs.22. A motor having a maximum power rating of8.1 x 10 watts is used to operate an elevatorwith a weight of 1.8 x 104 newtons. What isthe maximum weight this motor can lift at anaverage speed of 3.0 meters per second?(1) 6.0 x 10²³ N(3) 2.4 × 10 N(2) 1.8 x 104 N(4) 2.7 x 10* N38°FNch9:

Given For student-A Force applied by student B = 30 N Height upto which box is lifted = 0.40 m Time…

Answered: need help with number 20

Science

Physics

need help with number 20

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter7: Work, Energy, And Energy Resources

Section: Chapter Questions

Problem 41PE: (a) How long would it takea 1.50105 -kg airplane with engines that produce 100 MW of power to reach...

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