Assume that the distance that a car runs on 1 litre of petrol varies inversely as the square of the speed at which it is given. It gives a run of 25 km per litre at a speed of 36 km pH.At wat speed should it be driven to get a run of 36 km per litre?

• 30 kmph
  If the inverse relation of speed & distance or run can be represented with constant'k' then
  for Speed=36 kmph,Distance=25 km, So 25=k/(36^2), k=25*36^2
  So if speed=x, for distance=36 km then, 36=25*36^2/x^2 or x=30
• 11 years agoHelpfull: Yes(29) No(0)
• d=1/s2
  25*36*36=36*x2
  x2=25*36*36/36
  x=5*36/6
  x=30km ph
• 11 years agoHelpfull: Yes(4) No(0)
• 5km/hr
  X^2=K/Y
  K=X^2*Y
  for 36km/hr and run of 25km/lt
  36=K/25
  6^2=K/5^2
  K=6^2*5^2
  now for the ans:
  X=speed=Root over(K/36)=root over(6^2*5^2/6^2)=5*6/6= 5km/hr
• 11 years agoHelpfull: Yes(0) No(9)
• speed will be 5km
• 10 years agoHelpfull: Yes(0) No(1)
• its 30km/h.
• 10 years agoHelpfull: Yes(0) No(0)