work, energy problem - please provide explanation A 60 kg student is standing in

Question

work, energy problem - please provide explanation

A 60 kg student is standing in the train station next to her 10 kg suitcase when her train is called. (A) Estimate how much work she does picking up the suitcase. (B) She sprints 2 m, accelerating herself and her suitcase at 0.1 m/s2. How much force does she exert? (C) How much work does she do in this 2 m? (D) She now continues running at constant speed for 10 m to the train. How much work does she do in this 10 m? (E) What is her final kinetic energy as she reaches the train?

Explanation / Answer

(A) Work done in picking up the suitcase = m*g*h
Work done = 10 * 9.8 * h
Where h is the height she need to pick up.

(B)
Force = mass * acceleration
Force = 70kg * 0.1 m/s^2

Force = 7 N

Work done = Force * displacement
Work done = 7 * 2
Work done = 14 J

Final Kinetic Energy = 12 J

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.