Infosys Company Numerical Ability Algebra

There are two balls touching each other circumferencically. The radius of the big ball is 4 times the diameter of the small all. The outer small ball rotates in anticlockwise direction circumferencically over the bigger one at the rate of 16 rev/sec. The bigger wheel also rotates anticlockwise at N rev/sec. What is 'N' for the horizontal line from the centre of small wheel always is horizontal.

Read Solution (Total 5)

Here w (angular velocity is given) which is inversely proportional to radius
r.

i.e w α 1/r

Let w1 r1 w2 r2 be measures of Small circle and big circle respectively

hence w1 α 1/r1......................(1)

& w2 α 1/r2....................(2)

taking ratio of eqn 1 & 2we get

w1/w2=r2/r1

hence 16/N=8*r1/r1.............(r2=8r1)

on solving

N=2
14 years agoHelpfull: Yes(4) No(1)

2 rev/sec
15 years agoHelpfull: Yes(3) No(1)
4rev/sec
14 years agoHelpfull: Yes(1) No(2)
.25 or 1/4 rev/sec
14 years agoHelpfull: Yes(0) No(2)
1/4 rev/sec
14 years agoHelpfull: Yes(0) No(1)

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