The discussion focuses on solving a physics problem involving the calculation of velocity using the equations for potential energy (PE = MGH) and kinetic energy (KE = 1/2 x m x v^2). Participants clarify that the formula V = d/t is only applicable under constant velocity conditions, emphasizing the importance of accounting for acceleration in projectile motion. The correct velocity is determined to be approximately 20.98 m/s, derived from the kinetic energy formula. This highlights the necessity of understanding the distinction between speed and velocity in physics problems.
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The above formulas are very important to solving this problem.rqureshi24 said:
Be careful with that one. v = d/t only applies for constant velocity (i.e. if a = 0). But acceleration is involved with this problem. The projectile is certainly not moving at a constant velocity.
Oh, thank you so much for the tidbit. My physics teacher never explained to us like that. It's true that you learn something new everyday. :)
It's not 20 m/s, it's 20.976 and rounded to 20.98, isn't it because speed & velocity are the same thing?
I wish I thought of that earlier, now I got the correct answer using that formula! I feel so dumb for wasting so much time trying to figure it out.If you've already found KE, then use your KE = ½mv2 formula. Solve for v.