Basic Physics for the Utterly Clueless

Here at the Antisocial Network, we firmly believe that there are some questions that cannot be answered. No, we're not getting all metaphysical, and no, we're not talking about weird jokey questions like, "Do you walk to work or carry your lunch?" In fact, we're thinking of questions that contain so little information that one would need to be omniscient to craft an answer. eHow.com's Kimberly Dyke is most definitely not omniscient, based on her attempt to address "How to Find Speed from Distance and Mass," which now languishes at SportsRec.com for reasons unknown.

No way could Dyke (surprise, surprise: a liberal arts grad) give an accurate answer and still collect her stipend; because, "You can't!" is only two words and she needed 300 or so. That's why Kimmie did the next best thing: she went to the MSU¹ zone. Dyke opened by telling us that,

"Mathematics instructs us that speed = distance/time."

Right away, we knew this was going to be good, 'cause mathematics does not "instruct" that relationship, physics does. Oh, well, Kim still had to figure out how to get to mass from time, which is where she punted. Yup, Kim decided that the OQ wanted to know the average speed of a falling object, which allowed her to say,

"The mass amount does not change the formula because all objects accelerate at the same rate when falling downward."

Duh: as if an object could fall upward² or sideways... Anyway, Kimmie then went through a long, drawn-out process to use the formula,

v_f² – vi² = 2ad

Why Dyke decided to use that formula is beyond us. Clearly, she had no idea what she was saying (or trying to say), especially since seemed to think that,

"...acceleration equals -9.8 meters per second since it is a free fall."

First, you dumbass, the constant g is not negative³ and second, where did you get the notion that the OQ was talking about free fall? and third, you fool, the value of g is 9.8 m/sec²! That's not to mention that the quantity d is the displacement, and nowhere did anyone say anything about the object's displacement. Arbitrarily assigning it a value of 0.05 is not helpful.

And finally, Dyke instructs her readers to

"Take the final velocity/speed amount, or 0.99 meters per second, and plug it into the basic formula for speed: speed = distance/time..."

Even though nowhere has anyone said squat about time!

We repeat, oh Dumbass of the Day, you don't have enough information to calculate speed if all that is given are mass and distance. You must either know the context or have additional measurements. Throwing in a physics formula what you don't understand that introduces quantities that are neither constants nor givens is not answering the poor person's question. Sheesh.

¹ MSU: Making Shit Up.
² Actually, an object "falling upward" has negative acceleration...
³ The final velocity is a negative number because it is a downward vector, you moron.

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