Question

A helicopter is ascending vertically with a speed of 5.15 m/s At a height of 109 m above the Earth, a package is dropped from the helicopter Part A How much time does it take for the package to reach the ground? (Hint What is ty for the package? Express your answer to three significant figures and include the appropriate units. НА ? t = 42.3 s Submit Previous Answers Rescuest Answer X Incorrect; Try Again: 5 attempts remaining < Return to Assignment Provide Feedback

Answer 1

s=displacement

u=initial velocity

t=time taken to reach ground

a=acceleration

Using kinematic equation,

s=ut+1/2at²

Here,

u=velocity of package= velocity of the helicopter (As it is dropped from it)= 5.15 (j) m/sec

s= 109(-j) m

a=acceleration due to gravity= g= 9.8(-j) m/s²

-109= 5.15t-1/2*9.8t²

4.9t²-5.15t-109=0

By solving we get,

t= -4.22sec, 5.27 sec

Time is positive =t= 5.27sec