A man drops a baseball from the edge of a roof on a building. At exactly the same time, another man throws a baseball vertically up toward the man on the roof in such a way that the ball just barely reaches the roof. Does the ball from the roof reach the ground before the ball from the ground reaches the roof, or is it the other way around?
2006-08-31 04:35:26 · 11 answers · asked by Anonymous in Science & Mathematics ➔ Physics
same time....same gravity. So both balls are accelerating at the same speed. The one going up to the roof is slowing down at the same rate the ball going down is accelarating. The trick here is the speed of the ball going up in the accelration equation stars with a negative number that is the speed it is rising at when tossed. We know it perfectly reaches the top of the roof..so when it gets there is ti going 0. The ball on the roof stars at 0 but accelrates down and will stop when it hits the ground. So the ball that was dropped will be going the same speed when it hits that ground as the ball that was tossed up to the roof started at.
2006-08-31 04:40:46 · answer #1 · answered by Scott A 2 · 1⤊ 0⤋
If the dropped ball is measured from the same point that the man on the ground throws the ball upward (meaning they travel the same distance) then Scott* is correct. Mobi Guru made a mistake in reading the question. The ball from above is not thrown, it is dropped, hence the starting velocity is 0.
The ball dropped ends with the same velocity as the ball thrown up. We know this because we are told that the ball thrown up reaches the roof with a velocity of 0. The same accelleration is acting on both balls and they travel the same distance (presumed).
On the other hand, as PanamaJack points out, if the man on the roof is laying down and the man on the ground is standing up, the the ball thrown upward will have a shorter distance to travel.
I suspect that within the context of this question, both balls are released/thrown from people standing upright and of similar height. The whole point of this physics exercise is to demonstrate that direction is irrelevant in this type of situation.
2006-08-31 06:50:56 · answer #2 · answered by sparc77 7 · 0⤊ 0⤋
hmmm, have to put on my thinking cap. Unfortunately I can't find it so I'll just take a stab at it. If I recall, objects fall at roughly the same rate (a penny and a body falling from the Empire State Building would hit at the same time I believe). That said, the volicity to keep the ball from just reaching the roof would probably allow the ball being dropped to hit the ground first. Just a guess though. Didn't feel like breaking out the books and brushing off the dust.
2006-08-31 04:45:12 · answer #3 · answered by BrianR 2 · 0⤊ 0⤋
The ball from the roof reaches the ground before the other ball makes it up to the roof. As the ball goes downward it is building up speed and momentum as it is being puller down to the ground by gravity as well as the force used to throw the ball down.
The ball the if thrown up feels the sae pull of gravity and therefore loses momentum from the original burst of energy that threw it up.
2006-08-31 04:42:28 · answer #4 · answered by Penelope's Mom 3 · 0⤊ 0⤋
The ball from the roof reaches the ground first. The ball from the ground would reach the roof first if it was thrown faster than 9.8 meters per second squared (the speed of gravity).
2006-08-31 04:42:10 · answer #5 · answered by minna 2 · 0⤊ 0⤋
ball from the ground reaches the roof first
2006-08-31 04:40:40 · answer #6 · answered by Arron never walk's alone 4 · 0⤊ 0⤋
ball from roof reach ground first.
for both the balls, two forces are acting. The force of the throw, and the gravitational pull.
assuming the two persons throw the ball with same force, for the ball comming down, both forces are acting down
for the ball going up, the gravitational pull opposes the throwing force.
for ball falling down, acceleration is
f/m + g
for ball goin up, acceleration is
f/m - g
[ m- mass of ball, f- throwing force ]
more acceleration means more distance covered in less time.
2006-08-31 05:10:48 · answer #7 · answered by MobiGuru 2 · 0⤊ 0⤋
ball from roof reaches ground first
2006-08-31 04:39:35 · answer #8 · answered by Anonymous · 0⤊ 0⤋
ball from the roof reaches the first . whan the ball is thrown from the roof it undercomes the gravitation pull,while another ball is going retarded and its speed will slow in comparision to another ball.so i think ball from the roof reaches first
.
ok
2006-08-31 05:11:51 · answer #9 · answered by Kirat K 2 · 0⤊ 0⤋
The upward-bound ball would get there first becasue, if thrown, it starts several feet above the ground.
2006-08-31 04:56:59 · answer #10 · answered by PanamaJack 2 · 0⤊ 0⤋