Posted by **prve** on Wednesday, October 22, 2008 at 3:53pm.

How many secons apart should two balls be released so that a ball being deopped from a height of H reaches the ground at the same time as a ball dropped from a height of 5H?

- physics -
**GK**, Wednesday, October 22, 2008 at 4:48pm
I do not believe the question can be answered with a specific value. Here are my reasons:

H = gt^2/2

t = sqrt[2H/g]

Let the time for 5H = t'

5H = gt'^2/2

t' = sqrt[10H/g] = sqrt(5)*sqrt[2H/g]

The ratio of the two times is:

t'/t = sqrt(5)*sqrt[2H/g] / sqrt[2H/g] = sqrt(5)

or

t' = t*sqrt(5)

The 2nd ball must be released ( t' - t ) seconds later. The actual number of seconds depends on the value of H:

( t' - t ) = sqrt(5)*sqrt[2H/g] - sqrt[2H/g]

or

( t' - t ) = sqrt[2H/g]*[sqrt(5)-1]

- physics -
**prve**, Wednesday, October 22, 2008 at 5:25pm
Could you simplify your answer into simple words

## Answer this Question

## Related Questions

- Physics - The Colliding Balls: A ball is released from rest at a height h above ...
- Physics - Two balls are connected by a string that stretches over a massless, ...
- physic - Two balls are conneted by a string that stretches over a massless, ...
- physics - two balls are dropped to the ground from different heights. one ball ...
- physics - Two balls are dropped, one from height H and the other from a height ...
- PHYSICS - A BALL IS DROPPED A HEIGHT AT THE SAME TIME AS ANOTHER BALL IS ...
- 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 blue ball is thrown upward with an initial speed of 19.6 m/s, from ...
- phy - A blue ball is thrown upward with an initial speed of 20.6 m/s, from a ...

More Related Questions