Question
1. If the change in position delta(x) is related to velocity v (w/ units of m/s) in the equation delta(x)=Av, the constant A has which dimension?
a. m/s^2
b. m
c. s
d. m^2
2. If a is acceleration (m/s^2), delta(v) is change in velocity (m/s), delta(x) is change in position (m), and delta(t) is the time interval (s), which equation is NOT dimensionally correct?
a. delta(t) = delta(x)/v
b. a = v^2/delta(x)
c. delta(v)=a/delta(t)
d. delta(t)^2=2delta(x)/a
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With number 1, I'm just not really sure. I think the unit for delta(x) is throwing me off a little.
For number 2, I know what it's asking, but I'm not too good at finding dimensionally correct equations. I'm leaning toward d, however. I don't see time getting squared. A little help, please?
Thanks!
a. m/s^2
b. m
c. s
d. m^2
2. If a is acceleration (m/s^2), delta(v) is change in velocity (m/s), delta(x) is change in position (m), and delta(t) is the time interval (s), which equation is NOT dimensionally correct?
a. delta(t) = delta(x)/v
b. a = v^2/delta(x)
c. delta(v)=a/delta(t)
d. delta(t)^2=2delta(x)/a
---
With number 1, I'm just not really sure. I think the unit for delta(x) is throwing me off a little.
For number 2, I know what it's asking, but I'm not too good at finding dimensionally correct equations. I'm leaning toward d, however. I don't see time getting squared. A little help, please?
Thanks!
Answers
bobpursley
on the first deltax has units of meters.
on the second. Put the dang units for each in, and just reduce to see if it matches.
For instance:
a. s=m/(m/s)= s
duh, those match.
now do the rest
on the second. Put the dang units for each in, and just reduce to see if it matches.
For instance:
a. s=m/(m/s)= s
duh, those match.
now do the rest