how many rotations per minute must a wheel of diameter 1.5m make to achieve a speed of 45 kmph?

• 159.09 rotation/minute
  
  Given speed =45 kmph, so required speed per minute=45000/60=750 m.
  Distance covered in 1 rotation of wheel =Pi*diameter=Pi*1.5 m.
  So rotation /minute Required =750/(Pi*1.5)=750/[(22/7)*1.5]=159.09
• 8 years agoHelpfull: Yes(27) No(0)
• d=1.5m
  
  C = pi * d
  
  C = 4.71 m
  
  45000/4.71 =
• 8 years agoHelpfull: Yes(4) No(13)
• Distance covered in 1 rotation by the wheel of 1.5m dia. =4.71m
  and time taken to complete one rotation at the speed of 45kmph i.e. 12.5m/s=(4.71/12.5)=0.3768s
  Therefore in 0.3768sec 1 rotation completes at a speed of 45kmph.
  hence in 60 sec total no of rotations=(1/0.3768)*60=159.23
  approx 159 rotations in 1min.
• 8 years agoHelpfull: Yes(4) No(0)
• s= 45kmph, = 45000m/60 = 750
  distance covered in one rotation is pi*d=pi*1.5
  s=d/t=159.9
• 8 years agoHelpfull: Yes(1) No(2)
• 80 rotations/minute
  Given speed = 45kmph = 45000mph = 45000/60 meters per minute = 750 m per minute
  In a rotation of wheel it will cover a distance of its circumference = 2*pi*radius = 2*3.14*1.5 = 9.42m
  so rotations required to 750 m = 750/9.42 = 79.617 ~~ 80 rotations per minute
• 8 years agoHelpfull: Yes(0) No(4)