Are my dimensional analysis question correct

AI Thread Summary
The discussion centers on the correctness of several dimensional analysis equations involving area, volume, speed, and density. The first equation incorrectly calculates the exponent on time, while the second miscalculates the length exponent, leading to an incorrect total. The third equation is deemed nonsensical in its original form. Clarifications emphasize the importance of understanding exponent laws in dimensional analysis. Overall, the provided equations contain errors that need correction for accurate dimensional analysis.
JakePearson
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are these dimensional analysis questions correct

A = area
V = volume
v = speed
p = density

1. VA / v = L3 L2 L-1 T-1 = L4T-1

2. V2/3 A = (LT-1)2/3 L2 = L2/3 T-2/3 x L2 = L10/3T-2/3

3. 3A3 + 2V2 = A3 = L6
V2 = (L/T)2 = L2T-2 = L4T-2

are these correct
 
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For the first one, you made a mistake on the exponent on T. 1/[velocity] has dimensions of [time]/[length].

For the second one, you made a mistake on the L exponent. (2 + 6 is not equal to 10).

For the third one, the original equation doesn't make sense.
 
for;
v2/3A

i got an answer of = L4/3T-2/3

is this correct
 
No. Do you understand the laws of exponents? When you multiply two powers, you ADD their exponents. For example:

axay = ax+y
 
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