Question

diameter of a wheel is 140cm.how many revolutions must the bus make to keep certain speed of 66kmph

Answer 1

first find radius which is 70 now we will find how much distance it goes in one revolution, which is 2πr and thereby 2×(22÷7)×70=440cm and in km, it is 0.0044km hence when we will devide 66 by 0.0044km we will get the no. of revolutions which is 15000