Thread: Physics Dimensional Analysis problem

(a) Suppose that the displacement of an object is related to time according to the expression
x = Bt^2. What are the dimensions of B?
1)L^2/L
2)T^2/L
3)L × T^2
4)L/T^2
5) L/T


(b) A displacement is related to time as x = A sin(2πft), where A and f are constants. Find the dimensions of A. [Hint: A trigonometric function appearing in an equation must be dimensionless.]
1)L/T
2)T/L
3)L
4)L × T

Hey guys I've used the site in the past and it has helped me tremendously. I'm now in a physics class and its going to be a long uphill struggle for me. These are 2 problems out of 15 from some homework I have and if someone can break it down for me that would be more than wonderful.

Originally Posted by FactoringAnguish

(a) Suppose that the displacement of an object is related to time according to the expression
x = Bt^2. What are the dimensions of B?
1)L^2/L
2)T^2/L
3)L × T^2
4)L/T^2
5) L/T

is a displacement so its dimensions are . so you have a dimensional expression:



so:



CB

Originally Posted by CaptainBlack

is a displacement so its dimensions are . so you have a dimensional expression:



so:



CB

B= L/T^2 so #4 yes? I was so caught up with breaking down B into its own components rather than solving for B.