An object was thrown vertically up and allowed to fall down. The acceleration of it will be -10m/s, when it is moving up and the acceleration will be 10m/s, when it is moving down. Why isn't the acceleration 0m/s at the highest point.

Question

irishboy123 · Answer

if [and clearly this is hypothetical and plain wrong]  at the peak of flight, acceleration is actually zero, the the object will "freeze" at that point :-)  it will be stuck there forever ie it's velocity is zero and acceleration is zero.... or until another force acts upon it....

anonymous · Answer

I didn't understand

anonymous · Answer

How can there be another force because weight is the only force in this instance

irishboy123 · Answer

i didn't say there was another force !!!  i was saying that in your analysis the object should freeze unless some force acted on it.

if that is confusing, forget about it and think about the key question - why the object does not freeze.  because you say that its velocity is zero and its acceleration is zero.  so it must freeze....surely?!?!  it is stuck at v = 0 forever.....

and if you don't get this way of thinking, then just keeping mind that gravity doesnt get switched off.  gravity is always switched on, and F = ma is always true.  so object is always accelerating [or decelerating].

anonymous · Answer

I got it tks

irishboy123 · Answer

cool 😀

mrnood · Answer

OK - you have also made a basic error in your first assertion:

the acceleration is -10 m/s^2 AT ALL TIMES.
It does NOT change from - to + when th edirection changes.

It is the VELOCITY that changes direction, NOT the acceleration

mrnood · Answer

You have also got the units incorrect too:

acceleration is in m/s^2  NOT m/s