There are two balls touching each other circumferentially. The radius of the big ball is 4 times the diameter of the small all. The outer small ball rotates in anticlockwise direction circumferentially 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.

• 2
• 15 years agoHelpfull: Yes(3) No(0)
• If both rotates anticlockwise, there will be one infinitesimally small point of time, where the line joining won't be horizontal. Still, if only the position is checked at end of each second only, then the following might seem correct.
  
  Let radius of small wheel be 1 unit. So, radius of big wheel is 4*(2*1) = 8 units.
  Circumference of small wheel = 2*pi*1 = 2*pi.
  Circumference of big wheel = 2*pi*8 = 16*pi.
  Small wheel makes 16 rev/sec means, it travels 16*2*pi units of distance along its circumference. Which is twice the circumference of big wheel. So, if the big wheel is stationary, the sma
• 15 years agoHelpfull: Yes(0) No(3)
• As small wheel always make 2 complete revolutions around bigger wheel, the value of N should be such that, it must appear stationary. i.e., it must make complete revolutions and no fractional revolutions. So, N can be any whole number. i.e., N = 0, 1, 2, 3, ...
• 15 years agoHelpfull: Yes(0) No(3)
• 4rev/sec
• 15 years agoHelpfull: Yes(0) No(3)
• 64
• 15 years agoHelpfull: Yes(0) No(3)
• area of the smaller is less than larger circle by 16.
  this means that for smaller one 1revolution/sec=> to maintain the same horizontal axis it should be 4 times faster. hence
  16*4=64
  other wise the area of sector concept.
• 11 years agoHelpfull: Yes(0) No(1)