Physics ~please help me~

1.) Two people of the same mass climb the same flight of stairs. The first person climbs the stairs in 25 s; the second person does so in 35 s.
a) Which person does more work?Explain
b) Which person produces more power?Explain

2.) Lee pushes a 20 kg mass 10 m across a floor with a horizontal force of 80 N. Calculate the amount of work Lee does.

  1. 👍 1
  2. 👎 0
  3. 👁 668
  1. 1a) W1=W2 = mgh
    2a) P1 > P2 , mgh/25 >mgh/35

    2) W=Fs=80•10 =800 J

    1. 👍 1
    2. 👎 0
  2. The work done = potential energy gained = m g h.
    That is the same for both since m, g and h are the same for both

    The power is the work per unit time.

    Power = m g h/t
    so smaller t ---> bigger power

    1. 👍 1
    2. 👎 0
  3. Calculate the work done when a person push acar from stationany position to a

    distance of 50m appliny a. force of 200n.

    1. 👍 0
    2. 👎 0

Respond to this Question

First Name

Your Response

Similar Questions

  1. Language Arts

    Read this excerpt from A Girl from Yamhill. In the morning I descended from the bedroom by sliding down the banister railing, which curved at the end to make a flat landing place just right for my bottom. At night I climbed the

  2. physics

    At what rate is a 60.0-kg boy using energy when he sprints up a flight of stairs 10.0 m high in 8.00 s? A. 75.0 W B. 48.0 W C. 735 W D. 480 W E. 4.80 kW

  3. physics

    A new record for running the stairs of the Empire State Building was set on February 3, 2003. The 86 flights, with a total of 1576 steps, was run in 9 minutes and 33 seconds. If the height gain of each step was 0.20 m, and the

  4. math

    a rabbit climb up a flight of 10 stairs and can only hop 1 or 2 steps each time. he never hops down, only up. How many ways can the rabbit hop up the flight of 10 steps?

  1. physics

    A passenger on a boat moving at 1.70 m/s on a still lake walks up a flight of stairs at a speed of 0.60 m/s. The stairs are angled at 45° pointing in the direction of motion as shown in figure below. Write the vector velocity of

  2. Physics

    A girl whose weight is 30 N runs up a flight of stairs 5 m in 6 s. What is her average power


    A) The average power output of the human heart is 1.33 watts. How much energy does the heart produce in a day? B) Compare the energy found in part (a) with the energy required to walk up a flight of stairs. Estimate the height a

  4. Physics

    A woman runs up a flight of stairs. The gain in her gravitational potential energy is 6500 J. If she runs up the stairs at half the speed, what is her gain in gravitational potential energy?

  1. physics

    if you exert a force of 500N to walk 4M up a flight of stairs in 4S , how much power do you use?

  2. physics

    A 680 newton student runs up a flight of stairs 3.5 m high in 11.4 seconds. The student takese 8.5 seconds to run up the same flight of stairs during a second trial. 1)Find the work done by the 680 N student in climbing the stairs

  3. Physics

    19. Two people of unequal mass are initially standing still on the ice with negligible friction. They then simultaneously push each other horizontally. Afterward, which of the following is true? * -The center of mass of the two

  4. discrecte structure

    Calvin stays on the 7th floor in his building. Between each floor, there are exactly 12 stairs. If he starts from the 1st floor and climbs his way up to the 7th floor, how many stairs does he climb?

You can view more similar questions or ask a new question.