Q43 of 63 Page 202

Fill in the Blanks

An ellipse is described by using an endless string which is passed over two pins. If the axes are 6 cm and 4 cm, the length of the string and distance between the pins are ____________.

a = 6, a2 = 36


b = 4, b2 = 16


b2 = a2 (1 - e2)


16 = 36 (1 - e2)


4 = 9 (1 - e2)





Hence the length of strings and distance between the pins is & respectively.


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