Is it accelerating when we throw it up? Is the acceleration constant no matter how high we throw the ball up? If an astronaout throws a ball in the space shuttle, is the ball acceleration?
2006-09-22 02:56:38 · 9 answers · asked by Jojomon 2 in Science & Mathematics ➔ Physics
Acceleration is just change in velocity. So slowing down and speeding up are both acceleration, because they are both changes in velocity. And turning a corner at constant speed is also acceleration, because acceleration is change in velocity and not change in speed. Velocity is speed AND direction. The distinction may seem trivial, but not if you are solving physics problems.
2006-09-22 03:00:35 · answer #1 · answered by campbelp2002 7 · 5⤊ 0⤋
Acceleration is simply causing an object to increase its velocity (an object in motion has a velocity) --"the rate of change of position along a straight line with respect to time" or change its state of rest by applying a force that is greater than the forces already acting on it. A falling ball is acted upon by the force of gravity and maybe some other propulsion and its velocity is accelerated until it reaches terminal velocity ( which is caused by other forces such as air pressure). Initially the act of throwing a ball creates a force that causes it to accelerate but soon enough resistance and gravity slow it down so it falls (or even slows it rate of falling if it was propelled intially). The ball thrown in the space shuttle is initially accelerated. I have a feeling that you want to ask another question but don't know what, however this answers what you asked. Right?
2006-09-22 10:10:34 · answer #2 · answered by Nightstalker1967 4 · 1⤊ 0⤋
If you throw a ball it is subject to the earths gravitational constant wich is -9.98m/s, whatever way you throw it.
There are formulaes to find the acceleration of your ball:
1) Vf=Vi+gt
2) a=Vf-Vi/t
3) If you have or need the distance "d"
d=1/2 (Vf+Vi) *t
a: is the acceleration
Vf: is the final velocity
Vi: isthe initial velocity
g: is the gravitional constant.
(on earth g is -9.98m/s)
and t is time
the / is the divisor
In space an object will keep the initial speed it was given -pushed or thrown- its initial velocity will remain constant.
Unless it bumps into another object, then it will either crash into it or orbit it, the segond object will then affect its speed.
In the case of an astronaut throwing a ball from the space shuttle, the ball will orbit the shuttle at a constant speed.
2006-09-22 10:10:06 · answer #3 · answered by Yahoo! 5 · 0⤊ 0⤋
The ball is only accelerating with respect to the earth's frame of reference.
If you were inside the ball, unable to see outside, you would feel no acceleration. The ball whould be following a straight line and a constant speed as far as you could discern.
2006-09-22 11:39:38 · answer #4 · answered by Holden 5 · 0⤊ 0⤋
In MLB batters use the expression "jump" on the fastball or "giddyup". A ball cannot leave the hand of a pitcher and speed up. They are just comparing the relative speed to what they expect to see. Thus even though the ball is slowing down its still accelerating between the pitcher and the batter.
Go BlueJays
2006-09-22 10:06:50 · answer #5 · answered by Anonymous · 0⤊ 0⤋
Acceleration is the rate of change of velocity. That means, for each second that the ball travels, how much does it speed up or slow down and at what rate? When you throw a ball in the air it leaves your hand at a certain velocity and the starts to slow down. Why? Well, it's due to gravity. But how much does gravity slow the ball down? Scientists have measured this and found out that this "acceleration" due to gravity is about - 9.8 m/sec^2. That means that for every second the ball travels up, it slows down by 9,8m/sec. If you threw the ball straight up at 29.4m/sec (or about 60mph) after 1 sec it would be traveling 19.6m/sec, after 2 sec it would be going 9.8m/sec and after 3 sec it would be at rest. Notice even though the ball is at rest after 3 seconds, it is still "accelerating" because the force of gravity is still causing the ball's velocity to change. After 4sec, the ball is coming back down at 9.8m/sec, after 5 it is at 19.6 m/sec and when it hits the ground it is again going at 29.4 m/sec. We say that the ball was under "constant" acceleration because the same force of gravity acted on the ball the entire trip both up and down. In the space shuttle or in any other place in outer space where there is no gravity, there would be no acceleration on the ball at all. Whatever velocity it left your hand at, it would remain going at that velocity until some other force acted on it. No change in velocity-no acceleration. That is one of Newtons laws. Remember-- the acceleration due to gravity is -9.8m/sec^2.. If an object is going away from earth it slows at that rate. if it is coming back down to earth it speeds up by 9.8m/sec every second.
2006-09-22 10:36:54 · answer #6 · answered by True Blue 6 · 1⤊ 0⤋
According to newton's 2nd law magnitude of force is given by F=m*a where m=mass, a=acceleration
also according to newton's law of gravitation, the gravitational force between two objects would increase if they are brought nearer to each other.
hence when a ball is falling, gravitational force on it increases continuously.
according to F=m*a, to increase F you need to increase m or a or both
as m cant increase a has to increase. hence we can say it is accelarating
2006-09-22 10:31:31 · answer #7 · answered by pragyp 2 · 0⤊ 0⤋
both accelerations
2006-09-25 11:14:32 · answer #8 · answered by Anonymous · 0⤊ 0⤋
because it is
2006-09-22 10:35:37 · answer #9 · answered by rwbblb46 4 · 0⤊ 0⤋