Physics

posted by .

A sniper fires a bullet at 120 m/s at 30° above the horizontal from the roof top of a 35 m high parking garage. If the bullet strikes the level ground beside the parking garage:

a) How long was the bullet in the air?

b) How far from the base of the parking garage did the bullet land?

c) At what angle did the bullet land?

  • Physics -

    Vo = 120m/s[30o]
    Xo = 120*cos30 = 103.9 m/s.
    Yo = 120*sin30 = 60 m/s.

    a. Y = Yo * g*Tr = 0
    Tr=-Yo/g = -60/-9.8 = 6.12 s. = Rise time.

    h = ho + (Y^2-Yo^2)/2g
    h = 35 + (0-(60^2))/-19.6 = 218.7 m.
    Above gnd.

    h = 0.5g*t^2 = 218.7
    4.9t^2 = 218.7
    t^2 = 44.63
    Tf = 6.68 s. = Fall time.

    Tr+Tf = 6.12 + 6.68 = 12.8 s. = Time in
    air.

    b. d = Xo*(Tr+Tf) = 103.9m/s * 12.8s =
    1330 m.

    c. Y^2 = Yo^2 + 2g*h
    Y^2 = 0 + 19.6*218.7 = 4286.52
    Y = 65.5 m/s.

    Tan A = Y/Xo = 65.5/103.9 = 0.63041
    A = 32.2o

  • Physics -

    TYPO: Change Y = Yo*g*Tr = 0 to
    Y = Yo + g*Tr = 0

  • Thanks Henry -

    Thanks Henry,

    You're a good guy!

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Physics

    A thief is trying to escape from a parking garage after completing a robbery, and the thief’s car is speeding (v = 17.5 m/s) toward the door of the parking garage. When the thief is L = 14 m from the door a police officer flips a …
  2. Physics

    a rifle is fried from the top of a building 220 meters high with an initial velocity of 425 m/s at an angle of 12.0 degrees above the horizontal. a. how long will it take for the bullet to reach the ground?
  3. Microeconomics

    1.You plan a major adventure trip for the summer. You won’t be able to take your usual summer job that pays $6,000, and you won’t be able to live at home for free. The cost of your travel on the trip will be $3,000, film and videotape …
  4. physics

    A toy rocket is shot vertically from the base of a multiple level parking garage. the rockets height in feet is modeled by the equation h(T)= -16T squared+ 128 T, where T is the time in seconds if the rocket just reaches the top of …
  5. Physics

    A sniper fires a bullet at 120 m/s at 30° above the horizontal from the roof top of a 35 m high parking garage. If the bullet strikes the level ground beside the parking garage:
  6. Physics (URGENT!!!)

    A sniper fires a bullet at 120 m/s at 30° above the horizontal from the roof top of a 35 m high parking garage. If the bullet strikes the level ground beside the parking garage: a) How long was the bullet in the air?
  7. Math

    A parking garage is changing its parking fees for a week long festival. The function below represents the cost to park in the garage as a function of time (days into the festival). Piece wise c(t) = 10; 0 <= t <= 2 10; 2 < …
  8. math

    A parking garage is changing its parking fees for a week long festival. The function below represents the cost to park in the garage as a function of time (days into the festival). Piece wise c(t) = 10; 0 <= t <= 2 10; 2 < …
  9. math

    A parking garage is changing its parking fees for a week long festival. The function below represents the cost to park in the garage as a function of time (days into the festival). Piece wise c(t) = 10; 0 <= t <= 2 10+ t; 2 < …
  10. math

    A parking garage is changing its parking fees for a week long festival. The function below represents the cost to park in the garage as a function of time (days into the festival). Piece wise c(t) = 10; 0 <= t <= 2 10+ t; 2 < …

More Similar Questions