what is the velocity of a ball right before it hits the ground if it falls from a 2.5 m bookshelf?

Question

what is the velocity of a ball right before it hits the ground if it falls from a 2.5 m bookshelf?

in progress 0
Đan Thu 4 years 2021-08-21T21:11:02+00:00 1 Answers 26 views 0

Answers ( )

  1. thachthao
    0
    2021-08-21T21:12:36+00:00
    Reply

    Answer:

    vf = 7 m/s

    Explanation:

    The final velocity of the ball right before it hits the ground can be found by using the third equation of motion:

    2gh = v_f^2 - v_i^2

    where,

    g = acceleration due to gravity = 9.81 m/s²

    h = height = 2.5 m

    vf = final velocity = ?

    vi = initial velocity =  0 m/s

    Therefore,

    2(9.81\ m/s^2)(2.5\ m) = v_f^2 - (0\ m/s)^2\\v_f = \sqrt{49.05\ m^2/s^2}\\

    vf = 7 m/s

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )