Can someone explain this to me please?

  • Thread starter gcombina
  • Start date
  • #1
gcombina
157
3
Warning: Non-descriptive thread title

Homework Statement


Which equation is valid only when the angular measure is expressed in radians?
a) α = Δθ / Δt

b) ω= Δω / Δt

c) ω^2 = ωo^2 + 2αθ

d) ω = Vt/r (here T is a subscript)

e) θ = 1/2αt^2 + ωαt

Answer is D but why??



Homework Equations



I know angles can be measured in either degrees or radians

The Attempt at a Solution



angular velocity = ? divided by radius

I guess I don't understand what Vt is
 

Answers and Replies

  • #2
Vagn
519
65

Homework Statement


Which equation is valid only when the angular measure is expressed in radians?
a) α = Δθ / Δt

b) ω= Δω / Δt

c) ω^2 = ωo^2 + 2αθ

d) ω = Vt/r (here T is a subscript)

e) θ = 1/2αt^2 + ωαt

Answer is D but why??



Homework Equations



I know angles can be measured in either degrees or radians

The Attempt at a Solution



angular velocity = ? divided by radius

I guess I don't understand what Vt is
How do you relate the length of an arc to the angle subtended by the arc and the radius? What should the units of each quantity be?
 
  • #3
gneill
Mentor
20,945
2,886
I guess I don't understand what Vt is
Presumably ##V_t## will be defined in the text surrounding the problem. In this context I would imagine that it represents the tangential velocity of a rotating object at distance r from the center of rotation.
 

Suggested for: Can someone explain this to me please?

Replies
2
Views
342
Replies
6
Views
618
Replies
12
Views
435
Replies
8
Views
434
Replies
15
Views
795
Replies
1
Views
465
Replies
1
Views
309
Replies
9
Views
952
Top