Quiz Discussion

Each wheel of a car is making 5 revolutions per second. If the diameter of a wheel is 84 cm, then the speed of the car in cm/sec would be :

• 1] 420 cm/sec
• 2] 264 cm/sec
• 3] 1000 cm/sec
• 4] 1320 cm/sec

There are 8 equidistant points A, B, C, D, E, F, G and H in the clockwise direction on the periphery of a circle. In a time interval t, a person reaches from A to C with uniform motion while another person reaches the point E from the point B during the same time interval with uniform motion. Both the persons move in the same direction along the circumference of the circle and start at the same instant. How much time after the start, will the two persons meet each other ?

• 1] 4t
• 2] 7t
• 3] 9t
• 4] Never

A person wishes to reach his destination 90 km away 3 hours but for the first half of the journey his speed was 20 km/hr. His average speed for the rest of the journey should be :

• 1] 4 km/hr
• 2] 0.75 km/min
• 3] 1 km/min
• 4] None of these

Two persons A and B start simultaneously from P and Q respectively. A meets B at a distance of 60m from P. After A reaches Q and B reaches P, they turn around and start walking in opposite direction, now B meets A at a distance of 40m from Q. Find distance between P and Q?

• 1] 160 m
• 2] 100 m
• 3] 140 m
• 4] 105 m
• 5] None of These

A cyclist moving on a circular track of radius 100 meters completes one revolution in 2 minutes. What is the average speed of cyclist (approx.)?

• 1] 314 m/min
• 2] 200 m/min
• 3] 300 m/min
• 4] 900 m/min
• 5] None of these

Two guns are fired from the same place at an interval of 6 minutes. A person approaching the place observes that 5 minutes 52 seconds have elapsed between the hearings of the sound of the two guns. If the velocity of the sound is 330 m/sec, the man was approaching that place at what speed (in km/h)?

• 1] 24 kmph
• 2] 27 kmph
• 3] 30 kmph
• 4] 36 kmph

A man can cross a downstream river by steamer in 40 minutes and same by boat in 1 hour. If the time of crossing Upstream by streamer is 50% more than downstream time by steamer and the time required by boat to cross same river by boat in upstream is 50% more than time required by in downstream. What is the time taken for the man to cross the river downstream by steamer and then return to same place by boat half the way and by steamer the rest of the way?

• 1] 85 minutes
• 2] 115 minutes
• 3] 120 minutes
• 4] 125 minutes
• 5] None of these

Two cars start simultaneously from cities A and B, towards B and A respectively, on the same route. Once the two cars reach their destinations they turned around and move towards the other city without any loss of time. The two cars continue shuttling in this manner for exactly 20 hours. If the speed of the car starting from A is 60km/hr and the speed of the car starting from B is 40km/hr and the distance between the two cities is 120 km, find the number of times the two cars cross each other?

• 1] 8
• 2] 10
• 3] 12
• 4] 20
• 5] Can't be determined

Two cars are moving with speed v1, v2 towards a crossing along two roads, If their distance from the crossing be 40 metres and 50 metres at an instant of time then they do not collide if their speeds are such that :

• 1]

  v1 : v2 =16 : 25

• 2]

  v1 : v2 e 4 : 5

• 3]

  v1 : v2 e 5 : 4

• 4]

  v1 : v2 e 25 : 16

A thief is noticed by a policeman from a distance of 200 metres the thief starts running and the policeman chases him. The thief and the policeman run at the rate of 10 km/hr and 11 km/hr respectively. What is the distance between them after 6 minutes ?

• 1] 100 m
• 2] 190 m
• 3] 200 m
• 4] 150 m