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Comparison of the moment of inertia for a 40/50 wheel fitted with 33 X 5 cord and balloon tyres.


Identifier  ExFiles\Box 53\2\  Scan033
Date  20th August 1923
  
X4565
20823
COMPARISON OF MOMENT OF INERTIA OF 40/50 WHEEL FITTED WITH 33 X 5 CORD AND BALLOON TYRES.
X4565
I = 32 (Wrt^2 / 4π^2 - Wr^2 / g)

Cord tyre
W = 9.75 lbs. wt.
r = 1.502 ft.
t = 3.06 secs.

I = 32 (9.75 X 1.502 X 3.06^2 / 40 - 9.75 X 1.502^2 / 32)
= 87.5 lbs. ft.^2 units.

Balloon Tyre.
W = 9.75
r = 1.575
t = 2.84

I = 32 [9.75 X 1.575 X 2.84^2 / 40 - 9.75 X 1.575^2 / 32]
= 74.5 lbs.ft. units.

Decrease 13 lbs. ft.^2 on 87.5 lbs.ft.^2 units.
= 14.88%

Rm. {William Robotham - Chief Engineer}
  
  
From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).


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