Angular Distance Homework: Solve Δθ in Radians & Degrees

  • Thread starter Thread starter randomjunebug
  • Start date Start date
  • Tags Tags
    Angular
AI Thread Summary
To find the angular distance (Δθ) in both radians and degrees when Bob's hand moves a distance equal to twice the radius of the steering wheel, the relationship S = r * Δθ can be applied. Given that S is twice the radius (2r), the equation simplifies to 2r = r * Δθ, leading to Δθ = 2 radians. Converting this to degrees, Δθ equals 2 * (180/π), which is approximately 114.59 degrees. The confusion arose from misapplying the circumference formula and the relationship between distance and angle. The correct interpretation shows that the angular distance is simply 2 radians or about 114.59 degrees.
randomjunebug
Messages
4
Reaction score
0

Homework Statement


When driving Bob turns the steering wheel so the distance his hand moves on the steering wheel's circumference is equal to twice the radius of the steering wheel. In both radians and degrees, what angular distance (Δθ) did the wheel turn?


Homework Equations


S=r*Δθ
C=2∏r
1 rev=2∏ rad=360°


The Attempt at a Solution


I know the ratio of the circumference to the radius is 2∏. My first attempt I tried to equate the S and C equations. 2∏r=r*Δθ which got rid of r and I did (1/2)(2∏) which just gave me pi and was wrong. I'm not sure how to solve this but I feel like I'm just missing something small.

I tried making up numbers to help me see it. I pretended r was 5. What I want is 2r, which would be 10. So C=2∏r=31.416. If I divide that by 2∏ I get just r. If I divide it by ∏, I get 2r. So it's still wrong and I'm not sure where to go from here. Any help is really appreciated, it bothers me that I'm missing something.
 
Physics news on Phys.org
If the drivers hand moves exactly r in distance, then the angle would be 1 radian, from the definition of the radian. So twice that distance gives 2 radians.
 
So it has nothing to do with pi. Well I feel silly ha.
Thank you for your help.
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top