• Support PF! Buy your school textbooks, materials and every day products Here!

Variables This should be easy -- Matched units on LHS & RHS?

  • Thread starter kng1994
  • Start date
  • #1
2
0
Variable Units
x Meters (m)
v Meters per second (m/s)
t seconds (s)
a Meters per second squared (m/s^2)


These variables appear in the following equations, along with a few numbers that have no units. In which of the equations are the units on the left side of the equals sign consistent with the units on the right side?



(a) x = vt
Yes or No?

(b) x = vt + 1/2 at^2
Yes or No?

(c) v = at
Yes or No?

(d) v = at + 1/2 at^3
Yes or No?

(e) v^3 = 2ax^2
Yes or No?

(f) t = square root(2x/a)
Yes or No?" itemprop="text">The following table lists four variables along with their units.


Variable Units
x Meters (m)
v Meters per second (m/s)
t seconds (s)
a Meters per second squared (m/s^2)


These variables appear in the following equations, along with a few numbers that have no units. In which of the equations are the units on the left side of the equals sign consistent with the units on the right side?



(a) x = vt
Yes or No?

(b) x = vt + 1/2 at^2
Yes or No?

(c) v = at
Yes or No?

(d) v = at + 1/2 at^3
Yes or No?

(e) v^3 = 2ax^2
Yes or No?

(f) t = square root(2x/a)
Yes or No?

A B C F are all yes's right and D and E are no's right? If this is correct can someone try walking me through how to show my work for my answer. I can just see with my eyes what is going to work with past experiences but no way to actually describe why.
 

Answers and Replies

  • #2
BiGyElLoWhAt
Gold Member
1,560
113
Try replacing all the variables with the units associated with it, then carry out the operations. For the first one:
x=vt
m=(m/s)*s
Does that work out?
 
  • #3
BiGyElLoWhAt
Gold Member
1,560
113
Also, yes.
 
  • #4
DrClaude
Mentor
7,172
3,317
kng1994, you have to use the homework template when posting a homework question and you absolutely have to write an attempt at a solution.
 
  • #5
BiGyElLoWhAt
Gold Member
1,560
113
kng1994, you have to use the homework template when posting a homework question and you absolutely have to write an attempt at a solution.
Seconded. I was tired last night and not paying attention, otherwise I would have (presumably) mentioned that.
While you have answers, those answers are not work.
 

Related Threads on Variables This should be easy -- Matched units on LHS & RHS?

Replies
1
Views
1K
  • Last Post
Replies
5
Views
3K
  • Last Post
Replies
15
Views
2K
Replies
3
Views
1K
  • Last Post
Replies
3
Views
1K
Replies
3
Views
466
  • Last Post
Replies
3
Views
1K
  • Last Post
Replies
2
Views
4K
Replies
3
Views
4K
  • Last Post
Replies
3
Views
3K
Top