Draw a sketch and also a good FBD to identify the relevant forces doing work. Pay attention to the units and positive or negative value of the quantities. 1. A football player pushes a tackling dummy forwards at a constant 0.85 m/s for 11 m using 7150 J of energy. The tackling dummy has a mass of 120 kg. a) Find the force the football player exerts. b) What is the frictional force the dummy exerts? c) What work is done by friction as the dummy is slid along the field for 11 m? d) Is the mass necessary for this question? If not, what force question could be asked that would require the mass of the dummy? 2. A person pushes on a hockey puck with their stick at an angle so the vertical force is 22 N [down] and the horizontal force is 45 N [forward]. Assume the ice is frictionless. a) What is the actual force the hockey player transmits to the puck? b) What is the work done by the person pushing the hockey stick if they push the puck for 3.0 s as it moves with a constant velocity of 22 m/s [forward]? c) What is the significance of the fact that both the horizontal force and motion are both forwards?

Draw a sketch and also a good FBD to identify the relevant forces doing work. Pay attention to the units and positive or negative value of the quantities. 1. A football player pushes a tackling dummy forwards at a constant 0.85 m/s for 11 m using 7150 J of energy. The tackling dummy has a mass of 120 kg. a) Find the force the football player exerts. b) What is the frictional force the dummy exerts? c) What work is done by friction as the dummy is slid along the field for 11 m? d) Is the mass necessary for this question? If not, what force question could be asked that would require the mass of the dummy? 2. A person pushes on a hockey puck with their stick at an angle so the vertical force is 22 N [down] and the horizontal force is 45 N [forward]. Assume the ice is frictionless. a) What is the actual force the hockey player transmits to the puck? b) What is the work done by the person pushing the hockey stick if they push the puck for 3.0 s as it moves with a constant velocity of 22 m/s [forward]? c) What is the significance of the fact that both the horizontal force and motion are both forwards?

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Description: Please help me with these two questions Draw a sketch and also a good FBD to identify the relevant forces doing work.Pay attention to the units and positive or negative value of the quantities.1. A football player pushes a tackling dummy forwards at

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 64PE: Integrated Concepts (a) What force must be supplied by an elevator cable to produce an acceleration...

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