Is Radians Dimensionless in Scientific Measurements?

  • Thread starter Thread starter .NoStyle
  • Start date Start date
  • Tags Tags
    Radius
AI Thread Summary
Radians are indeed considered dimensionless in scientific measurements, despite being derived from a length measurement, specifically the radius of a circle. The confusion arises from the relationship between radians and the radius, as the radius is a measure of length. The SI unit of length is the meter, but when measuring angles in radians, the units cancel out, resulting in a dimensionless quantity. This distinction is crucial for understanding how radians function in mathematical and scientific contexts. Ultimately, radians serve as a way to express angles without dimensions.
.NoStyle
Messages
35
Reaction score
0
I'm inclined to believe that radius is a measure of length, so doesn't that mean it's dimensional?

I am probably wrong...

thanks
 
Physics news on Phys.org
SI unit of length is meter, and yes, radius is a length, is defined as the line segment trough the center to any point of the circunference
 
Last edited:
.NoStyle said:
I'm inclined to believe that radius is a measure of length, so doesn't that mean it's dimensional?

I am probably wrong...

thanks

I think you're thinking of radians which in fact are dimensionless.
 
calef said:
I think you're thinking of radians which in fact are dimensionless.


shoot you're right, radians, not radius. Thanks you're right.
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
View full post »

Thread 'Egg Drop Challenge! Need ideas for winning designs'

I was thinking using 2 purple mattress samples, and taping them together, I do want other ideas though, the main guidelines are; Must have a volume LESS than 1600 cubic centimeters, and CAN'T exceed 25 cm in ANY direction. Must be LESS than 1 kg. NO parachutes. NO glue or Tape can touch the egg. MUST be able to take egg out in less than 1 minute. Grade A large eggs will be used.
View full post »

Similar threads

Show that the radius of the exoplanet is about 1/2 of Earth’s radius
Replies
2
Views
789
Dimensional Analysis: Solving Confusing Steps
Replies
4
Views
1K
Ruler measurements and knowing how many decimal places to include
Replies
9
Views
2K
Did my textbook make a mistake when writing these units?
Replies
5
Views
772
B Radian measure and real numbers
Replies
9
Views
2K
I Dimension of an Angle: Clarifying the SI Standard
Replies
1
Views
2K
Where are the waves out of phase with each other by π radians?
Replies
14
Views
2K
Finding slip-off angle for mass off of sphere?
Replies
7
Views
1K
Converting Chord Length to Radians: A Confusing Concept?
Replies
8
Views
2K
The components of force and velocity vectors in circular motion
Replies
11
Views
3K

Hot Threads

Recent Insights

Back
Top