Ask questions and get helpful answers.

a boy tosses a coin upward with a velocity of 14.7 m/s.

a. find the maximum height reached by the coin.
b. time of flight
c. velocity when the coin returns to the hand
d. suppose the boy failed to catch the coin and the coin goes to the ground, with what velocity will it strike the ground?the boy's hand is 0.49 m above the ground.

  1. 👍
  2. 👎
  3. 👁
  4. ℹ️
  5. 🚩

5 answers

  1. a) Use the formula; V^2=Vo^2=2g(y-yo)
    cancel V^2 and yo (because it is zero)
    -V0^2/2g=2gy/2g <-- Cancel 2g
    y=-Vo/2g=-(14.7 m/s2)/2(-9.8m/s^2)
    y=11.04m

    b)t=2y/Vo=2(11.04m)/14.7 m/s
    t=1.5s
    t^2(1.5)(2)
    =3s

    c)V^2=(2g)(yo)
    =2(-9.8 m/s^2)(-11.04)
    V^2= <SQUARE-ROOT>216.38
    =-14.71 m/s

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩
  2. v=u-gt or 0=14.7-9.81t
    t=14.7/9.81=1.498 say1.5 sec
    v^2=u^2-2gh or 0=14.7^2-2x9.81xh
    h=14.7^2/2x9.81=11m.
    Add 0.49m Total ht=11.49m
    On falling down, u=0
    v^2=0+2x9.81x11 or v=14.69 upto hand.
    v^2=0+2x9.81x11.49 or v=15.01m/s up to ground.

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩
  3. g = -9.8 m/s^2
    Vo = 14.7 m/s V = 0 m/s
    Yo = 0 m Y = 11.04 m
    To = 1.5 s T = 1.5 s

    a.) (V-Vo)/2g = (Y-Yo)
    y= (-216.09)/(-19.16)
    y= 11.04 m
    b.) V= Vo+gt
    0= 14.7 + (-9.8)(t)
    -14.7 = -9.8t
    t= 1.5 s
    total time = (1.5)(2)
    total time = 3 s
    c.) V= Vo+gt
    V= 0+(-9.8)(1.5)
    V= 14.7 m/s
    ~~~~~~~~~~~~~~~~~~~~~~~~~
    Yo = 11.04 + 0.49
    Yo = 11.53 m
    Vo = 0 m/s
    V = ???
    t = ???
    g = -9.8

    d.) V^2 = Vo^2 + 2g(Y-Yo)
    V^2 = 0 + 2(-9.8)(0-11.53)
    V^2 = (-19.6)(-11.53)
    V^2 = 225.988
    V = 15.03 m/s^2
    ~~~~~~~~~~~~~~~~~~~~~~~~~
    I'm not really sure about this one. The answer should be negative because of the downward velocity. But if the value was negative it would be imaginary because of the radical sign.

    Yo = 0 ; Y = 11.53

    V^2 = 0 + 2(-9.8)(11.53-0)
    V^2 = (-19.6)(11.53)
    (sqrt)V^2 = (sqrt)(-225.988)
    V = 15.03i m/s
    ~~~~~~~~~~~~~~~~~~~~~~~~~

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩
  4. Correction

    d.) V^2 = Vo^2 + 2g(Y-Yo)
    V^2 = 0 + 2(-9.8)(0-11.53)
    V^2 = (-19.6)(-11.53)
    V^2 = 225.988
    V = 15.03 m/s <---

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩
  5. What does the Yo represents?

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩

Answer this Question

Related Questions

Still need help?

You can ask a new question or browse existing questions.