FIGURE 2.1 (Continued)

17

c^2

c^2

c^1

c^1

r

r

r 1

R

I = r^4

I = 0.1098 (R^4 – r^4 )

= 0.3tr 13 (approx)

when is very small

0.283R^2 r^2 (R–r)

R+r

π

8

8

9 π

_

= 0.1098r^4

t

r 1

I

c 2

I

c 1

c 1

= 0.1908r^3

= 0.2587r^3

= 0.4244r

c 1 =

c 2 =R – c 1

4

3 π

R^2 + Rr + r^2

R + r

9 π^2 – 64

6 π

r = 0.264r

2 I

π (R^2 – r^2 )

t = 0.31r 1 (approx)

a

1 a

a

t

t

b 1 b

b

(approx)

(approx)

(approx)

I =πa =0.7854a^3 b

(^3) b
4
(a^3 b – a 13 b 1 )
=πa =0.7854a^2 b
(^2) b
4
I =π
4
= a(a + 3b)t
π
4
I
c
I
c
a
2
a
2
a + 3b
a + b
I
(πab – a 1 b 1 )
= a^2 (a + 3b)t

π
4