Calculating Rotational Speed of Car Tyres: How Many Spins in a Given Distance?

Click For Summary

Discussion Overview

The discussion revolves around calculating the rotational speed of a car tire based on its diameter and the distance traveled by the car. Participants explore how to determine the number of revolutions the tire makes over a given distance and the corresponding angular speed.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant suggests calculating the circumference of the tire and dividing the distance traveled by the car in one second by this circumference to find the number of revolutions per second.
  • Another participant confirms that the length of the car is not relevant to the calculation, emphasizing that the analysis can be done based on one wheel.
  • A participant presents a specific example with a car traveling 34 feet and a tire diameter of 28 inches, calculating approximately 4.64 revolutions and asking for confirmation of this result.
  • Another participant agrees with the calculated revolutions but questions whether the distance mentioned is the total distance traveled or the distance traveled in one second.
  • A participant comments on the flexibility of using total distance traveled over any time interval to calculate angular speed, mentioning that each rotation corresponds to 360 degrees.
  • One participant humorously expresses frustration with the units of feet and inches while discussing the calculations.
  • A later reply notes that the velocity of the tire at the point of contact with the road must be zero to avoid skidding, adding a condition to the discussion.

Areas of Agreement / Disagreement

Participants generally agree on the method of calculating the number of revolutions but there is some uncertainty regarding the interpretation of the distance traveled (total distance vs. distance per second). Additionally, the discussion includes varying perspectives on the relevance of the car's length and the conditions for calculating angular speed.

Contextual Notes

There are unresolved assumptions regarding the time interval for the distance traveled and the implications of using different units of measurement. The discussion does not clarify the exact conditions under which the calculations apply.

gmxplode
Messages
10
Reaction score
0
Rotational Speed of Car tyre?

hey guys i was trying to figure out this rotational speed of car tyre?...i have with me the diameter of the car tyre and the distance which it is traveling and the length of the car...so can anyone help? i need to find out how much times will the tyre spin and at what speed in that traveled distance?
 
Physics news on Phys.org


Just work out the circumference of the tyre. Then divide the distance traveled by the car in one second by the circumference. That will be the number of revs per second.
The length of the car is not relevant (you could go on just one wheel, if you could stay upright.).
 


sophiecentaur said:
Just work out the circumference of the tyre. Then divide the distance traveled by the car in one second by the circumference. That will be the number of revs per second.
The length of the car is not relevant (you could go on just one wheel, if you could stay upright.).

ok thanks for the information...so if the car is traveling 34 feet and the diameter is 28 inches then the result I am getting is 4.64 revolution which is equivalent to 1670 Degrees..is it correct?...
 


gmxplode said:
ok thanks for the information...so if the car is traveling 34 feet and the diameter is 28 inches then the result I am getting is 4.64 revolution which is equivalent to 1670 Degrees..is it correct?...

That looks good to me.
 


AlephZero said:
That looks good to me.

this 34 feet is the total distance traveled and not distance traveled in one second so is it still correct?
 


OMG, I'm laying in bed and the man wants me to do feet and inches.
But you can do total distance traveled in any time interval. If each rotation is 360 then the angular speed is revs per second / hour / week times 360.
G'night. :-)
 
sophiecentaur said:
OMG, I'm laying in bed and the man wants me to do feet and inches.
But you can do total distance traveled in any time interval. If each rotation is 360 then the angular speed is revs per second / hour / week times 360.
G'night. :-)
Ok thanks got ya...
 


Of course, the velocity that the tire is moving where it meets the road must be zero, or you'll be skidding :)
 

Similar threads

  • · Replies 26 ·
Replies
26
Views
7K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 20 ·
Replies
20
Views
4K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 49 ·
2
Replies
49
Views
6K
  • · Replies 46 ·
2
Replies
46
Views
12K
  • · Replies 13 ·
Replies
13
Views
8K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 19 ·
Replies
19
Views
2K
  • · Replies 7 ·
Replies
7
Views
5K