OpenEuphoria

Re: bullet code (was ICONS - dead horse)

• Posted by George Walters <gwalters at SC.RR.COM> Feb 07, 2000
• 359 views

David, the example you gave the velocity is straight up at 1000 ft/sec.
Gravity is slowing it down at 32ft/sec each second, so after one second the
height above the ground would be:

y = 1000 * 1 - .5 *32* 1* 1 = 984 ft high... which would be correct. Gravity
only would change it's velocity 32ft/sec each second. It would then take
1000/32 seconds for it to be stopped.. somewhere up in the air. 1000
feet/sec is quite fast (sound is approx 780 ft/sec).. so your bullet would
go quite far upwards (neglicting air drag).

You could figure how high it would go by using.... V = SQRT(2*G*H) or
solving for H

H = V*V / G and your example this would be 31,250 feet... which is
neglicting air drag which is quite subtantial at super sonic speeds. So the
31,250 would be quite unrealistic.

.. george


-----Original Message-----
From: George Walters <gwalters at SC.RR.COM>
To: EUPHORIA at LISTSERV.MUOHIO.EDU <EUPHORIA at LISTSERV.MUOHIO.EDU>
Date: Monday, February 07, 2000 8:27 PM
Subject: Re: bullet code (was ICONS - dead horse)


>you forgot 'G', it's 32ft/sec/sec
>
>
>-----Original Message-----
>From: David Roach <roachd_76 at YAHOO.COM>
>To: EUPHORIA at LISTSERV.MUOHIO.EDU <EUPHORIA at LISTSERV.MUOHIO.EDU>
>Date: Monday, February 07, 2000 8:23 PM
>Subject: Re: bullet code (was ICONS - dead horse)
>
>
>>Let's take your equation y = vy * t - .5 * t * t and let's add some
>>numbers.
>>velocity = 1000f/s
>>time = 1 second
>>
>>y = 1000f/s * 1s - .5 * 1s^2
>>y = 1000f - .5s
>>y = 999.5 f
>>
>>I just can't believe that anything will fall 999.5 feet in one second.
>>Plus velocity and gravity are independent of each other.
>>Could someone please clue us in to what we are talking about.
>>
>>roachd_76
>>George Walters <gwalters at SC.RR.COM> wrote:
>>
>>>Here are the correct equations:
>>>
>>>X = X0 + VX * T
>>>
>>>Y=Y0 +VY * T - .5G * T * T
>>>
>>>VX = V* COS(ANGLE)
>>>
>>>VY = V * SIN( ANGLE)
>>>
>>>V = initial velocity at some angle above the ground
>>>X0 AND Y0 are initial positions and could be zero
>>>
>>>..george
>>>