Question

A boy finds an abandoned mine shaft in the woods, and wants to know how deep the hole is. He drops in a stone, and counts 4 seconds before he hears the "plunk" of the stone hitting the bottom of the shaft. Approximately how deep is the shaft? Assume a gravitational acceleration of 9.8 m/s2 and no significant air resistance hint:.(Hint: d=at2/2)

Answer 1

h=ut+(1/2)at^2=0*t+(1/2)gt^2=0.5*9.8*t^2=0.5*9.8*4^2

Answer 2

tell me h=?

Answer 3

14 meters
24 meters
39 meters
78 meters its between these answers

Answer 4

ya answer is in ur optoins

Answer 5

plz use ur calculator to get the right answer

Answer 6

tell me how to start

Answer 7

0.5*9.8*16=?

Answer 8

thanks

Answer 9

did u get the result?

Answer 10

thanks for giving medal

Answer 11

no problemo