Posted by Dave on Thursday, November 15, 2012 at 11:33pm.
A red ball is thrown up off the edge of a building 10 m tall with an initial speed of 4 m/s.
A) how long does it take for the red ball to strike the ground below?
B) If a black ball is dropped off the edge of the same building, how many seconds after the release of the red ball must the black ball be released so that they strike the ground at the same time

PHYSICS Urgent help please  drwls, Friday, November 16, 2012 at 4:22am
A) Solve this equation for the time t:
Y = 10 + 4t 4.9 t^2 = 0
Take the positive root. There will be two solutions.
t = [4 sqrt(16 + 196)]/9.8
= 1.89 s
B)The black ball that is dropped requires t = sqrt(2H/g)= 1.43 s to fall
To hit the ground at the same time as the red ball, delay its release by 1.891.43 = 0.46 seconds
Answer This Question
Related Questions
 physics  A red ball is thrown up off the edge of a building 10 m tall with an ...
 Physics  A red ball is thrown down with an initial speed of 1.3 m/s from a ...
 physics  A red ball is thrown down with an initial speed of 1.2 m/s from a ...
 physics  A ball is thrown upward with an initial velocity of 6.0m/s by someone ...
 physics  A red ball is thrown down with an initial speed of 1.0 m/s from a ...
 Physics urgent pls!  A ball is tossed from an upperstorey window of a building...
 Physics  A red ball is thrown down with an initial speed of 1 m/s from a height...
 physics  A ball is thrown horizontally off the edge of a cliff with an initial ...
 Physics  A red ball is thrown down with an initial speed of 1.2 m/s from a ...
 physics  A red ball is thrown down with an initial speed of 1.4 m/s from a ...
More Related Questions