Three wheels can completed respectively 60, 36, 24 revolutions per minute . There is a red spot on each wheel that touches the ground at time zero . After how much time , all these spots will simultaneously touch the ground again ?

Three wheels can complete 40,24 and 16 revolutions per minute respectively.There is a red spot on each wheel that touches the ground at time zero.After how much time,all these spots will simultaneously touch the ground agots will simultaneously touch the ground again? 7(1)/(2)sec(b)18backslash sec(c)7(1)/(2)min (d) 18min

The radii of the front wheel and the rear wheel of a bike are 14 cm and 21 cm respectively. Rahul puts a red mark on the point of contact of each of the wheels with the ground when the bike is stationary. Once the bike start moving, then after what distance will the two red marks touch the ground again simultaneously? (a) 42 cm (b) 84 cm (c) 264 cm (d) 294 cm

A ball is thrown vertically upward with velocity 20 m//s from a tower of height 60 m. After how much time and with what velocity will it strike the ground?

Two pipe A and B can separately fill a cistern in 60 minutes and 75 minutes respectively . There is a third pipe at the bottom of the cistern to empty it, if all the three pipes are simultaneously opened, then the cistern is filled in 50 minutes . In how much time can the third pipe alone empty the cistern ?

Two pipes A and B can separately fill a cistern in 40 minutes and 30 minutes respectively. There is a third pipe in the bottom of the cistern to empty it. If all the three pipes are simultaneously opened, then the cistern is full in 20 minutes. In how much time, the third pipe alone can empty the cistern?

The wheels of a car of diameter 80cm each.How many complete revolutions does each wheel make in 10 minutes when the car is travelling at a speed of 66 km per hour?

The wheels of a car are of diameter 80cm each. How many complete revolutions does each wheel make in ten minutes when the car is traveling at the speed of 66km per hour?