Physics question about free falling object need help!?

Question

Need help on physics question A helicopter is ascending vertically with a speed of 4.00 m/s. At a height of 75 m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground?

Answer 1

You must solve this equation:

0.5*g*t²-4*t=75m

First part 0.5*g*t² is descendance due to gravity, second part -4*t is ascendance due to basic speed of the helicopter.

Where g is the earths gravity, 9.8 m/s².

You get: 4.9*x²-4x-75=0 which solves to 4.34 seconds. (Sounds reasonable)

Answer 2

Consider the vertical motion of the packet :

Initial velocity, u = 4 m/s            (as the helicopter is ascending in the upward direction)

a = -10 m/s                                (minus sign indicates downward direction)      

s = -75 m

Use the 2nd equation of motion :

s = ut + 1/2*a*t^2

t = 4.3 s

Hope this helps.

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Answer 3

i m not gonna do ur homework, dude!!!

Answer 4

18.75s

S = D/T

If I remember correctly