Ask Question
3 September, 05:03

The superhero Green Lantern steps from the top of a tall building. He falls freely from rest to the ground, falling half the total distance to the ground during the last 1.00 s of his fall.

What is the height h of the building?

+4
Answers (1)
  1. 3 September, 05:29
    0
    57.18 m

    Explanation:

    Given:

    - Distance traveled s (t_f) = 0.5*h

    - Time in which the distance was traveled t_-t = 1.0 s

    - Initial Velocity V_i = 0

    - Initial distance from ground s (0) = h

    Find:

    Height of the building h

    Solution:

    Using Equation of motion of free fall from rest:

    s (f) = s (0) + 0.5*g*t^2

    Evaluate time taken to reach 0.5*h height of the building:

    0.5*h = h - 0.5*9.81*t_1^2

    t_1 = sqrt (h / g)

    Evaluate time taken to reach bottom of the building:

    0 = h - 0.5*9.81*t_2^2

    t_2 = sqrt (2*h / g)

    Hence,

    t_2 - t_1 = 1

    sqrt (h / g) - sqrt (2*h / g) = 1

    Squaring both sides we get:

    h/g + 2h/g - 2*sqrt (2) * h/g = 1

    h (1+2-2sqrt (2)) = g

    h = g / (3-2sqrt (2))

    h = 57.18 m
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “The superhero Green Lantern steps from the top of a tall building. He falls freely from rest to the ground, falling half the total distance ...” in 📗 Physics if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers