Ask Question
22 September, 08:04

a street light is mounted at the top of a 15 foot pole. A man 6 ft tall walks away from the pole wit a speed of 7 ft/s along a straight path. How fast is the tip of his shadow moving when he is 40 ft from the pole

+4
Answers (1)
  1. 22 September, 08:52
    0
    16.3 ft/s

    Explanation:

    Let d=distance

    and

    x = length of shadow.

    Therfore,

    x = (d + x)

    = 6/15

    So,

    15x = 6x + 6d

    9x = 6d.

    x = (2/3) d.

    As we know that:

    dx=dt

    = (2/3) (d/dt)

    Also,

    Given:

    d (d) = dt

    = 7 ft/s

    Thus,

    d (d + x) = dt

    = (7/3) d (d/dt)

    Substitute, d = 7

    d (d + x) = 49/3 ft/s.

    Hence,

    d (d + x) = 16.3 ft/s.
Know the Answer?
Not Sure About the Answer?
Find an answer to your question ✅ “a street light is mounted at the top of a 15 foot pole. A man 6 ft tall walks away from the pole wit a speed of 7 ft/s along a straight ...” in 📘 Physics if you're in doubt about the correctness of the answers or there's no answer, then try to use the smart search and find answers to the similar questions.
Search for Other Answers