Please tell me that schools are really teaching that the force of gravity is 32 ft/s/s and you made the conversion yourself.....
Now what if the bullet was fired on a conveyor belt....
Taught in metric when I was in school
Physics Question
- Thread starter WolfLMM
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Taught in metric when I was in school
its actually decelerate and it is a type of acceleration, just in the form of slowing down rather than speeding up. acceleration encompasses all changes in velocity + or -
Back when I was in Physics in college. There was a question posed on a test that asked the following:
How do the accelerator, the brake pedal, and the steering wheel cause changes in velocity?
The first assumption is that letting off the accelerator does not cause the vehicle to loose speed.
The accelerator is obvious as it cause positive change in velocity. Acceleration
The brake pedal causes negative change in velocity. Deceleration
The steering wheel causes positive change in velocity in one direction and negative change in velocity in another. Hence it causes acceleration in one direction and deceleration in the other.
How do the accelerator, the brake pedal, and the steering wheel cause changes in velocity?
The first assumption is that letting off the accelerator does not cause the vehicle to loose speed.
The accelerator is obvious as it cause positive change in velocity. Acceleration
The brake pedal causes negative change in velocity. Deceleration
The steering wheel causes positive change in velocity in one direction and negative change in velocity in another. Hence it causes acceleration in one direction and deceleration in the other.
It does. The bullet is going neither up or down. The time is measurable.
The answer Always is incorrect.
Going up, going down it is accelerating. Once it hits the ground: zero, zip, nada.
So the answer is: Only while it is motion.
Definition for always: constantly: without variation or change, in every case. This is not the case once it hits the ground.
Then the word acceleration is a misnomer and realy means movement of any kind as you explane it. When you attend driving school and are told to deaccelerate it means nothing? It means slow down as you enter an apex.
I understand acceleration as a positive forward motion. When that motion starts to slow down, IMHO it is not acceleration any more and I don't care what your teachers told you.
I totaly understand the physics of the question and what you guys are trying to state, but in real life it is wrong as far as the way you use the word accelerate.
I understand acceleration as a positive forward motion. When that motion starts to slow down, IMHO it is not acceleration any more and I don't care what your teachers told you.
I totaly understand the physics of the question and what you guys are trying to state, but in real life it is wrong as far as the way you use the word accelerate.
Lol ok whatever you say. The bullet would float in mid air if it wasn't accelerating. I'm sorry but you are wrong. Obviously when the bullet hits the ground the problem is over lol.
Mike, you are right for most real world conversations you would say deceleration. But in the physics classroom, and a few other places, you need to say acceleration.
If bullet has no acceleration it will float in mid air. The bullet doesn't float, it reverses.
Never argue with gravity, it always wins.
What causes acceleration? Energy. When the energy ceases, motion eventualy comes to a hault, and you can call it gravity or anything you want but it is not acceleration anymore. Anything falling to the ground no matter what weight will hit the ground at the same time because of gravity.
What I think some of you guys are not getting is the way we use the word and the scientific understanding of the word as compared to real life use.
Wrong.
The bullet cannot float in air because it is heavier than air. So it stops for a short period and falls to the gound at the speed of gravity from which it cannot accelerate. And it will fall to the ground slower from this point than the speed that got it there. So how do we define the word accelerate if the bullet got to a point faster and dropped slower? Don't we need another word for this?
mike l. you just got to realize its in a classroom environment and ignore reality. that is why some engineers can't figure out why their junk blows up outside of the computer simulation and classroom environment. and the bullet would never stop unless you could stop spinning of the earth, so it will arch over, following the curve, up and over.
Mike, gravity is acceleration. 9.81m/sec/sec. That means for every se nod of free fall an object will increase it velocity by 9.81.
With no gravity a bullet can float in air.
How did we get to velocity? Acceleration? At the point of return when velocity stopped, the bullet falls, do we still call this acceleration when in fact the governing force is totaly different. Energy caused the climb to velocity and when energy stopped, gravity pulled it down at a controlled force. The bullet did not accelerate to the ground.
Gravity doesn't have a speed. There is an acceleration due to gravity which is why the bullet is always accelerating. If you define your coordinate system so that down is positive, the acceleration is positive and there is no deceleration.
Because acceleration is change in velocity divided by change in time. As soon as the bullet leaves the barrel of the gun the force of gravity acts on it, and it experiences acceleration towards the ground.
It's a very elementary question. The bullet doesn't know the earth is rotating. Earths rotation has no impact in this problem.
Ignore reality? Nah, the acceleration of gravity is the only thing keeping you in your seat.