A jet aeroplane travelling at the speed of 500 km/hr ejects its products of combustion at speed of 1500 km/hr relative to jet plane.

A jet aeroplane travelling at the speed of 500 km/hr ejects its products of combustion at speed of 1500 km/hr relative to jet plane.
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A jet aeroplane travelling at the speed of 500 km/hr ejects its products of combustion at speed ... latter with respect to an observer on the ground?
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The combined mass of car and passengers travelling at 72 km/hr is 1500 kg. Find the kinetic energy of this combined mass. (Formula: K =mv2 / 2k )  a. 300 kJ  b. 200 kJ  c. 500 kJ  d. None of the above

Description : The combined mass of car and passengers travelling at 72 km/hr is 1500 kg. Find the kinetic energy of this combined mass. (Formula: K =mv2 / 2k )  a. 300 kJ  b. 200 kJ  c. 500 kJ  d. None of the above

Last Answer : 300 kJ

An aeroplane A, is travelling in a straight line with a velocity of 300 km/hr with respect to Earth. Another aeroplane B, is travelling

Description : An aeroplane A, is travelling in a straight line with a velocity of 300 km/hr with respect to Earth. Another aeroplane B, is travelling

Last Answer : An aeroplane A, is travelling in a straight line with a velocity of 300 km/hr with respect to ... relative velocity of 100 km/hr with respect to A?

A train, travelling at a uniform speed for 360 km, would have taken 48 minutes less to travel the same distance if its speed were 5 km/hr more. Find the original speed of the train. -Maths 10th

Description : A train, travelling at a uniform speed for 360 km, would have taken 48 minutes less to travel the same distance if its speed were 5 km/hr more. Find the original speed of the train. -Maths 10th

Last Answer : Let the speed of train be x km/hr Distance to be travelled = 360km We know that, Time take by the train intially = If the speed was increased by 5km/hr Time taken by train = Difference in the time taken is 48 minutes, x2+5x -2250 = 0 (x+50)(x-45) Speed = 45 km/hr as speed cannot be negative

A boy sitting in a train which is travelling at 25 km/hr observes that a goods train travelling in opposite direction, takes 4.5 seconds to pass him. If the train is 140 m long, find its speed. A) 77km/hr B) 79km/hr C) 87km/hr D) 89km/hr

Description : A boy sitting in a train which is travelling at 25 km/hr observes that a goods train travelling in opposite direction, takes 4.5 seconds to pass him. If the train is 140 m long, find its speed. A) 77km/hr B) 79km/hr C) 87km/hr D) 89km/hr

Last Answer : ANSWER : C Explanation: Relative speed = distance / time = (140 / 4.5) m/s = 31.11 m/s Convert m/s into km/hr  31.11 m/s = (31.11 * 18 / 50 km/hr  = (560 / 5) km/hr  = ... train (by sitting) = (112 - 25) km/hr = 87 km/hr  Therefore the speed of goods train is 87 km/hr.

Ganesh is travelling on his motorbike and has calculated to reach golden temple at 8 p.m if he travels at 30 km/hr; he will reach there at 6 p.m if he travels at 45 km/hr. At what speed must he travel to reach the golden temple at 7 p.m? a) 36 b) 46 c) 32 d) 30

Description : Ganesh is travelling on his motorbike and has calculated to reach golden temple at 8 p.m if he travels at 30 km/hr; he will reach there at 6 p.m if he travels at 45 km/hr. At what speed must he travel to reach the golden temple at 7 p.m? a) 36 b) 46 c) 32 d) 30

Last Answer : A Let the distance travelled be x km x/30 – x/45 = 2 (3x – 2x) / 90 = 2 x/90 = 2 x = 180km Time taken to travel 180 km at 30 km/hr = 180 / 30 = 6 hrs So ganesh started 6 hrs before 8 pm That is 2 pm Required speed = distance / time =(180/5) =36 km/hr

A boat takes 38 hrs for travelling downstream from point p to point q and coming back to a point r midway between p and q. If the velocity of the stream is 8 km/hr and the speed of the boat in still water is 28 km/hr. What is the distance between p and q? A) 720 B) 640 C) 510 D) 450

Description : A boat takes 38 hrs for travelling downstream from point p to point q and coming back to a point r midway between p and q. If the velocity of the stream is 8 km/hr and the speed of the boat in still water is 28 km/hr. What is the distance between p and q? A) 720 B) 640 C) 510 D) 450

Last Answer : ANSWER: A Explanation: Speed downstream = (28 + 8)km/hr = 36 km/hr Speed upstream = (28 – 8)km/hr = 20 km/hr Let the distance between p and q be ‘x’km Then, x/36 + (x/2)/20 = 38 x/36 +x/40 = 38 19x = 13680 X = 720 km Therefore the distance between p and q is 720km

A truck of mass 5 ton is travelling on a horizontal road with 36 km hr^-1 stops on travelling 1 km after its engine fails suddenly.

Description : A truck of mass 5 ton is travelling on a horizontal road with 36 km hr^-1 stops on travelling 1 km after its engine fails suddenly.

Last Answer : A truck of mass 5 ton is travelling on a horizontal road with 36 km hr-1 stops on travelling ... similar distance same how much will the fraction be?

Water is flowing in a stream with velocity 5 km/hr in an easterly direction relative to the shore. Speed of a boat relative to still

Description : Water is flowing in a stream with velocity 5 km/hr in an easterly direction relative to the shore. Speed of a boat relative to still

Last Answer : Water is flowing in a stream with velocity 5 km/hr in an easterly direction relative to the ... , with what velocity will the boat actually travel?

Steam side heat transfer co-efficient in an evaporator is in the range of __________ kcal/hr.m2°C. (A) 10-50 (B) 100-500 (C) 1000-1500 (D) 5000-15000

Description : Steam side heat transfer co-efficient in an evaporator is in the range of __________ kcal/hr.m2°C. (A) 10-50 (B) 100-500 (C) 1000-1500 (D) 5000-15000

Last Answer : (D) 5000-15000

For design purposes, the normal rate of infiltration of ground water into the sewer, is A. 500 litres/km/cm B. 1000 litres/km/cm C. 1500 litres/km/cm D. 2000 litres/km/cm

Description : For design purposes, the normal rate of infiltration of ground water into the sewer, is A. 500 litres/km/cm B. 1000 litres/km/cm C. 1500 litres/km/cm D. 2000 litres/km/cm

Last Answer : ANS: D

Stopping distance of vehicles : When brakes are applied to a moving vehicle, the distance it travels before stopping is called stopping distance. It is an important factor for road safety and depends on the initial velocity ( v 0 ) and the braking capacity, or deceleration, ?a that is caused by the braking. A car travelling at speed 72km/hr suddenly applies the brake with the deceleration of 5m/s2. Find the stopping distance of the car -Science

Description : Stopping distance of vehicles : When brakes are applied to a moving vehicle, the distance it travels before stopping is called stopping distance. It is an important factor for road safety and depends on ... the brake with the deceleration of 5m/s2. Find the stopping distance of the car -Science

Last Answer : Here u=72 km/hr = 72×10003600m/s=2072×10003600m/s=20 m/s , v=0 a= -5 m/s2 Now using the relation v2=u2+2asv2=u2+2as 0=(20)2+2×(−5)×s0=(20)2+2×(−5)×s s=40ms=40m

If a train crosses a tree in 24 seconds while travelling at a speed of 90km/hr, then in how much time will the train cross a telegraph post of length 1200m at same speed? A) 26 sec B) 48 sec C) 72 sec D) 38 sec

Description :  If a train crosses a tree in 24 seconds while travelling at a speed of 90km/hr, then in how much time will the train cross a telegraph post of length 1200m at same speed? A) 26 sec B) 48 sec C) 72 sec D) 38 sec 

Last Answer : ANSWER:C Explanation: Speed of the train = 90 km/hr Converting the speed into m/sec 90 km/hr = (90* 5/18)m/s = 25m/s length of the train = distance travelled we know distance = speed * ...  Time = distance / speed  = ( 1800/25) sec  = 72 seconds  Hence the required answer is 72 seconds

At the same speed a boat travelling 50km upstream and 78km downstream in 16hrs. Also it can travel 70km upstream and 104km downstream, in 22hrs at the same speed of the stream is. A) 5km/hr B) 3km/hr C) 4km/hr D) 2km/hr

Description : At the same speed a boat travelling 50km upstream and 78km downstream in 16hrs. Also it can travel 70km upstream and 104km downstream, in 22hrs at the same speed of the stream is. A) 5km/hr B) 3km/hr C) 4km/hr D) 2km/hr

Last Answer : ANSWER : C

The sound power level of a jet plane flying at a height of 1 km is 160 dB. What is the maximum sound pressure level on the ground directly below the plane assuming that the aircraft radiates sound equally in all directions? A. 59.1 dB B. 69.1 dB C. 79.1 dB D. 89.1 dB

Description : The sound power level of a jet plane flying at a height of 1 km is 160 dB. What is the maximum sound pressure level on the ground directly below the plane assuming that the aircraft radiates sound equally in all directions? A. 59.1 dB B. 69.1 dB C. 79.1 dB D. 89.1 dB

Last Answer : D. 89.1 dB

The sound intensity received from the nearby jet plane is 12.6 µW/m2 and that from another jet plane some distance away is 0.45 µW/m2 . Find the relative loudness of the two. A. 14.0 dB B. 14.5dB C. 12.5 D. 14.5

Description : The sound intensity received from the nearby jet plane is 12.6 µW/m2 and that from another jet plane some distance away is 0.45 µW/m2 . Find the relative loudness of the two. A. 14.0 dB B. 14.5dB C. 12.5 D. 14.5

Last Answer : B. 14.5dB

At the alternate aerodrome, the commander of a turbojet engine aeroplane should have a fuel quantity (final reserve) sufficient for flying during: a. 30 minutes at holding flight speed at 1,500 ft b. 45 minutes at holding flight speed at 1,500 ft c. 30 minutes at cruising speed d. 45 minutes at cruising speed

Description : At the alternate aerodrome, the commander of a turbojet engine aeroplane should have a fuel quantity (final reserve) sufficient for flying during: a. 30 minutes at holding flight speed at 1,500 ft b. 45 ... speed at 1,500 ft c. 30 minutes at cruising speed d. 45 minutes at cruising speed

Last Answer : a. 30 minutes at holding flight speed at 1,500 ft

“Tsunamis can travel at speeds of about 500 miles or 805 kilometres an hour, almost as fast as a jet plane.”

Description : “Tsunamis can travel at speeds of about 500 miles or 805 kilometres an hour, almost as fast as a jet plane.”

Last Answer : The impact of earthquakes are what typically generate tsunami waves. The biggest tsunami ever recorded hit southwest shoreline of Alaska in 1958. The force of the wave was measured at 1720 feet (524 meters) high. This is the largest wave that has ever been known to humans! 

A car travelling at a speed of 60 km/hour is braked and comes to rest 6 seconds after the brakes are applied. The minimum coefficient of driction between the wheels and the road would be a.0.107 b.0.3 c.0.283 d.0.417 e.0.5

Description : A car travelling at a speed of 60 km/hour is braked and comes to rest 6 seconds after the brakes are applied. The minimum coefficient of driction between the wheels and the road would be a.0.107 b.0.3 c.0.283 d.0.417 e.0.5

Last Answer : c. 0.283

Anjana walked at 4 kmph for a certain part of his journey and took an auto, travelling at 25 kmph for the rest of the journey. If he took 42 minutes for the entire journey, what part of the journey did he walk given that his average speed for the entire journey was 10 kmph? a) 2 km b) 1.5 km c) 3.5 km d) 4 km e) 1 km

Description : Anjana walked at 4 kmph for a certain part of his journey and took an auto, travelling at 25 kmph for the rest of the journey. If he took 42 minutes for the entire journey, what part of the journey did he walk given that his ... journey was 10 kmph? a) 2 km b) 1.5 km c) 3.5 km d) 4 km e) 1 km

Last Answer : Total time = 42 minutes = 0.7 hours. Average speed = 10 kmph Total distance = 0.7×10 = 7 km Let distance walked = W W/4 + (7-W)/25 = 0.7 Solving W = 2 Answer: a)

An aircraft is travelling at 100kts forward speed on a 3° glidescope. What is its rate of descent? a. 500 ft/min b. 300 ft/min c. 250 ft/min d. 600 ft/min

Description : An aircraft is travelling at 100kts forward speed on a 3° glidescope. What is its rate of descent? a. 500 ft/min b. 300 ft/min c. 250 ft/min d. 600 ft/min

Last Answer : a. 500 ft/min

An aircraft is travelling at 100kts forward speed on a 3° glidescope. What is its rate of descent? a. 500 ft/min b. 300 ft/min c. 250 ft/min d. 600 ft/min

Description : An aircraft is travelling at 100kts forward speed on a 3° glidescope. What is its rate of descent? a. 500 ft/min b. 300 ft/min c. 250 ft/min d. 600 ft/min

Last Answer : a. 500 ft/min

The frequency of a wave travelling at a speed of 500 ms-1 is 25 Hz. Its time period will be ______. (i) 20 s (ii) 0.05 s (iii) 25 s (iv) 0.04 s

Description : The frequency of a wave travelling at a speed of 500 ms-1 is 25 Hz. Its time period will be ______. (i) 20 s (ii) 0.05 s (iii) 25 s (iv) 0.04 s

Last Answer : (iv) 0.04 s

The velocity of jet of water travelling out of opening in a tank filled with water is proportional to (A) Head of water (h) (B) h² (C) V/T (D) h/2

Description : The velocity of jet of water travelling out of opening in a tank filled with water is proportional to (A) Head of water (h) (B) h² (C) V/T (D) h/2

Last Answer : Answer: Option C

Speed of sound in water is 1500 m s-1, depth of water when reflected sound waves are detected after 0.40 s is A. 700 m B. 600 km C. 600 m D. 750 km

Description : Speed of sound in water is 1500 m s-1, depth of water when reflected sound waves are detected after 0.40 s is A. 700 m B. 600 km C. 600 m D. 750 km

Last Answer : 600 m

A balanced three-phase, 50 Hz voltage is applied to a 3 phase, 4 pole, induction motor. When the motor is delivering rated output, the slip is found to be 0.05. The speed of the rotor m.m.f. relative to the rotor structure is (A) 1500 r.p.m. (B) 1425 r.p.m. (C) 25 r.p.m. (D) 75 r.p.m.

Description : A balanced three-phase, 50 Hz voltage is applied to a 3 phase, 4 pole, induction motor. When the motor is delivering rated output, the slip is found to be 0.05. The speed of the rotor m.m.f. relative to the rotor structure is (A) 1500 r.p.m. (B) 1425 r.p.m. (C) 25 r.p.m. (D) 75 r.p.m.

Last Answer : (D) 75 r.p.m.

The expenditure on fuels in running a train varies as the square of its speed measured in km/hr and it is Rs. 48 per hour at the speed of 16 km/hr. If

Description : The expenditure on fuels in running a train varies as the square of its speed measured in km/hr and it is Rs. 48 per hour at the speed of 16 km/hr. If

Last Answer : The expenditure on fuels in running a train varies as the square of its speed measured in km/ ... hour find the best speed of the train economically.

A motor car starts with the speed of 70 km/hr with its speed increasing every two hours by 10 kmph. In how many hours will it cover 345 kms? A.4 hrs B.4 hrs 5 mins C.4 1/2 hrs D.2 hrs E.None of these

Description : A motor car starts with the speed of 70 km/hr with its speed increasing every two hours by 10 kmph. In how many hours will it cover 345 kms? A.4 hrs B.4 hrs 5 mins C.4 1/2 hrs D.2 hrs E.None of these

Last Answer : Answer - C (4 1/2 hrs) Explanation - Distance covered in first 2 hours = (70 x 2) km = 140 km Distance covered in next 2 hours = (80 x 2) km = 160 km Remaining distance = 345 - (140 + 160) = 45 km. Speed in the ... ..1 hr 45km .? ?=45/90hr=1/2hr Total time taken = 2 + 2 +1/2=4 (1/2)hrs

A bike starts with a speed of 60 km/hr at 8a.m. Due to the problem in engine it reduces its speed as 20 km/hr for every 1 hour. After 9 am, the time taken to covers 15 km is: a) 13 minutes and 20 seconds b) 15 minutes and 09 seconds c) 18 minutes and 15 seconds d) 22 minutes and 30 seconds

Description : A bike starts with a speed of 60 km/hr at 8a.m. Due to the problem in engine it reduces its speed as 20 km/hr for every 1 hour. After 9 am, the time taken to covers 15 km is: a) 13 minutes and 20 seconds b) 15 minutes and 09 seconds c) 18 minutes and 15 seconds d) 22 minutes and 30 seconds

Last Answer : 15 min

A royal enfield bike starts with the speed of 210 km/hr with its speed increasing every 2 hrs by 30km/hr, in how many hrs will it cover 1035km? a) 2 1/2 hr b) 4 1 /2 hr c) 6 1 /2 hr d) 7 1 /2 hr

Description : A royal enfield bike starts with the speed of 210 km/hr with its speed increasing every 2 hrs by 30km/hr, in how many hrs will it cover 1035km? a) 2 1/2 hr b) 4 1 /2 hr c) 6 1 /2 hr d) 7 1 /2 hr

Last Answer : B Distance covered in 1st 2 hrs = (210*2)km =420km Distance covered in next 2 hrs = (240*2)km =480km Remaining distance = 1035 – (420+480) =1035 – 900 =135km Speed in 5th hr = 270 km/hr Time taken to cover 135 km = 135/270 = ½ hr Total time taken = (2+2+1/2) =4 ½ hrs

A hare is spotted by a tiger from a distance of 50 metres. When the tiger starts a chase, the hare also starts running. If the speed of the hare be 4 km/hr and that of a tiger 5 km/hr, how far the hare will have run before its over taken? a) 100m b) 200m c) 300m d) 400m

Description : A hare is spotted by a tiger from a distance of 50 metres. When the tiger starts a chase, the hare also starts running. If the speed of the hare be 4 km/hr and that of a tiger 5 km/hr, how far the hare will have run before its over taken? a) 100m b) 200m c) 300m d) 400m

Last Answer : B Relative speed of the tiger = (5-4)km/hr =1 km/hr Time taken by tiger to cover 50 m, =(50/1000)hr =1/20hr In 1/20 hrs, the tiger cover a distance of (4*1/20)km =1/5km =>(1/5*1000)m =200m

Diameter of pully should be such that it gives the best speed of ........meter/minute at full throtlle: A)500 b)950 C)1500 d)2000

Description : Diameter of pully should be such that it gives the best speed of ........meter/minute at full throtlle: A)500 b)950 C)1500 d)2000

Last Answer : b)950

An automobile weighing 2800 lb and travelling at 30 miles/hr, hits a depression in the road which has a radius of curvature of 50 ft. What is the total force to which springs are subjected. a.8230 lb b.6170 lb c.2800 ib d.107 dynes e.3280 lb

Description : An automobile weighing 2800 lb and travelling at 30 miles/hr, hits a depression in the road which has a radius of curvature of 50 ft. What is the total force to which springs are subjected. a.8230 lb b.6170 lb c.2800 ib d.107 dynes e.3280 lb

Last Answer : b. 6170 lb

A train travels between two stations 15 km apart in 18 minutes. If the train accelerates for a part of journey uniformly followed by uniform retardation, the maximum speed attained by the train during the journey will by a.125 km/hr b.107 dynes c.80 km/hr d.100 km/hr e.60 km/hr

Description : A train travels between two stations 15 km apart in 18 minutes. If the train accelerates for a part of journey uniformly followed by uniform retardation, the maximum speed attained by the train during the journey will by a.125 km/hr b.107 dynes c.80 km/hr d.100 km/hr e.60 km/hr

Last Answer : d. 100 km/hr

A train travels between two stations 15 km, apart in 18 minutes. If the train accelerates for a part of journey uniformly followed by uniform relardation, the maximum speed attained by the train, during, the journey, will be a.60 km/hr b.80 km/hr c.125 km/hr d.100 km/hr e.107 dynes

Description : A train travels between two stations 15 km, apart in 18 minutes. If the train accelerates for a part of journey uniformly followed by uniform relardation, the maximum speed attained by the train, during, the journey, will be a.60 km/hr b.80 km/hr c.125 km/hr d.100 km/hr e.107 dynes

Last Answer : d. 100 km/hr

how long would it take to drive 3636 km at a speed of 100 km/hr?

Description : how long would it take to drive 3636 km at a speed of 100 km/hr?

Last Answer : 3636/100 = 36.36 hours

A car moving with a speed of 40 km/hr can be stopped by applying brakes after at least 2 m. If the same car is moving with a speed of 80 km/hr. What i

Description : A car moving with a speed of 40 km/hr can be stopped by applying brakes after at least 2 m. If the same car is moving with a speed of 80 km/hr. What i

Last Answer : A car moving with a speed of 40 km/hr can be stopped by applying brakes after at least 2 m. If the same car is moving ... A. 2 m B. 4 m C. 6 m D. 8 m

A car moves at a constant speed of 60 km/hr for 1 km and 40 km/hr for next 1 km. What is the average speed of the car?

Description : A car moves at a constant speed of 60 km/hr for 1 km and 40 km/hr for next 1 km. What is the average speed of the car?

Last Answer : A car moves at a constant speed of 60 km/hr for 1 km and 40 km/hr for next 1 km. What is the average speed of the car?

A car travels at a speed of 50 km/hr for 30 minutes, at 30 km/hr for next 15 minutes and then 70 km/hr for next 45 minutes.

Description : A car travels at a speed of 50 km/hr for 30 minutes, at 30 km/hr for next 15 minutes and then 70 km/hr for next 45 minutes.

Last Answer : A car travels at a speed of 50 km/hr for 30 minutes, at 30 km/hr for next 15 minutes and ... next 45 minutes. What is the average speed of the car?

A car is running on a road at a uniform speed of 60 km/hr. What is the net resultant force on the car?

Description : A car is running on a road at a uniform speed of 60 km/hr. What is the net resultant force on the car?

Last Answer : Equal to zero

A belt conveyor used for the transportation of materials can (A) Run upto 1 km (B) Travel at a speed upto 300 metres/minute (C) Handle materials upto 5000 tons/hr (D) All (A), (B) and (C)

Description : A belt conveyor used for the transportation of materials can (A) Run upto 1 km (B) Travel at a speed upto 300 metres/minute (C) Handle materials upto 5000 tons/hr (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

A boat goes 30 km upstream and 44 km downstream in 10 hours. In 13 hours it can go 40 km upstream and 55 km downstream. Then what is the speed of the stream? (a) 3km/hr (b) 5km/hr (c) 6km/hr (d) 7km/hr

Description : A boat goes 30 km upstream and 44 km downstream in 10 hours. In 13 hours it can go 40 km upstream and 55 km downstream. Then what is the speed of the stream? (a) 3km/hr (b) 5km/hr (c) 6km/hr (d) 7km/hr

Last Answer : (a) 3km/hr

A boat goes 30 km upstream and 44 km downstream in 10 hours. In 13 hours it can go 40 km upstream and 55 km downstream. Then what is the speed of the stream? (a) 3km/hr (b) 5km/hr (c) 6km/hr (d) 7km/hr

Description : A boat goes 30 km upstream and 44 km downstream in 10 hours. In 13 hours it can go 40 km upstream and 55 km downstream. Then what is the speed of the stream? (a) 3km/hr (b) 5km/hr (c) 6km/hr (d) 7km/hr

Last Answer : (a) 3km/hr

If the speed of boat is 5 km/hr and speed of stream is 2 km/hr. What is the speed of the boat in Upstream? a) 5km/hr b) 2km/hr c) 7km/hr d) 3km/hr

Description : If the speed of boat is 5 km/hr and speed of stream is 2 km/hr. What is the speed of the boat in Upstream? a) 5km/hr b) 2km/hr c) 7km/hr d) 3km/hr

Last Answer : d) 3km/hr

If the speed of the boat is 5 km/hr and the speed of stream is 2 km/hr, what is the speed of the boat Downstream? a) 5km/hr b) 2km/hr c) 7km/hr d) 3km/hr

Description : If the speed of the boat is 5 km/hr and the speed of stream is 2 km/hr, what is the speed of the boat Downstream? a) 5km/hr b) 2km/hr c) 7km/hr d) 3km/hr

Last Answer : c) 7km/hr

A man on tour travels first 160 km at 64 km/hr and the next 160 km at 80 km/hr. The average speed for the first 320 km of the tour is: a) 35.55 km/hr b) 36 km/hr c) 71.11 km/hr d) 71 km/hr e) 69.69km/hr

Description : A man on tour travels first 160 km at 64 km/hr and the next 160 km at 80 km/hr. The average speed for the first 320 km of the tour is: a) 35.55 km/hr b) 36 km/hr c) 71.11 km/hr d) 71 km/hr e) 69.69km/hr

Last Answer : Total time taken = (160/64) + (160/80) = 9/2 hrs. Avg Speed – 320 × (2/9) km/hr = 71.11km/hr Answer: c)

Busses start from a bus terminal with a speed of 20 km/hr at intervals of 10 minutes. What is the speed of a man coming from the opposite direction towards the bus terminal if he meets the buses at intervals of 8 minutes? a) 3 km/hr b) 4 km/hr c) 5 km/hr d) 7 km/hr e) None of these

Description : Busses start from a bus terminal with a speed of 20 km/hr at intervals of 10 minutes. What is the speed of a man coming from the opposite direction towards the bus terminal if he meets the buses at intervals of 8 minutes? a) 3 km/hr b) 4 km/hr c) 5 km/hr d) 7 km/hr e) None of these

Last Answer : Distance covered in 10 minutes at 20 kmph = distance covered in 8 minutes at (20+x) kmph 20× 10/60=8/60(20+x) 200 = 160 + 8x 8x = 40 x=40/8=5 kmph Answer: c)

A boat running downstream covers a distance of 20 km in 5 hours while for covering the same distance upstream, it takes 10 hours. What is the speed of the stream? a) 2km/hr b) 4km/hr c) 1km/hr d) 1.5 km/hr e) None of these

Description : A boat running downstream covers a distance of 20 km in 5 hours while for covering the same distance upstream, it takes 10 hours. What is the speed of the stream? a) 2km/hr b) 4km/hr c) 1km/hr d) 1.5 km/hr e) None of these

Last Answer : c Rate of downstream=(20 / 5 ) kmph= 4kmph Rate of upstream =( 20/10) kmph= 2kmph Therefore Speed of the stream= (1/2)(4 - 2) kmph= 1 kmph

A train overtakes two persons walking along a railway track. The first one walks at 4.5 km/hr. The other one walks at 5.4 km/hr. The train needs 8.4 and 8.5 seconds respectively to overtake them. What is the speed of the train if both the persons are walking in the same direction as the train? A.59 km/hr B.65 km/hr C.70 km/hr D.81 km/hr E. None of these

Description : A train overtakes two persons walking along a railway track. The first one walks at 4.5 km/hr. The other one walks at 5.4 km/hr. The train needs 8.4 and 8.5 seconds respectively to overtake them. What is the speed ... as the train? A.59 km/hr B.65 km/hr C.70 km/hr D.81 km/hr E. None of these

Last Answer : Answer-D (81 km/hr) Explanation4.5 km/hr =(4.5 x 5/18)m/sec =5m/4sec = 1.25 m/sec, and 5.4 km/hr =(5.4 x 5/18)m/sec =3m/2sec = 1.5 m/sec. Let the speed of the train be x m/sec. Then, (x - 1.25) ... - 12.75 => 0.1x = 2.25 => x = 22.5 Therefore Speed of the train =(22.5 x18 /5)km/hr = 81 km/hr.

A train 125 m long passes a man, running at 5 kmph in the same direction in which the train is going, in 10 seconds. The speed of the train is: A.35 km/hr B.50 km/hr C.48 km/hr D.55 km/hr E.None of these

Description : A train 125 m long passes a man, running at 5 kmph in the same direction in which the train is going, in 10 seconds. The speed of the train is: A.35 km/hr B.50 km/hr C.48 km/hr D.55 km/hr E.None of these

Last Answer : Answer – B (50 km/hr) Explanation – Let speed be S Relative speed = total lengths/time [ in this case man length is neglible compare to train so neglected] (S – 5) x 5/18 = 125 /10 S- 5 = (125/10)x(18/5) S-5 = 45 S=50 km/hr

There is road besides a river. Two friends started from a place P, moved to a shopping mall situated at another place Q and then returned to P again. One of them moves on a cycle at a speed of 12 km/hr, while the other sails on a boat at a speed of 10 km/hr. If the river flows at the speed of 4 km/hr, which of the two friends will return to place P? A. Both B. Boater C. Cyclist D. None of these

Description : There is road besides a river. Two friends started from a place P, moved to a shopping mall situated at another place Q and then returned to P again. One of them moves on a cycle at a speed of 12 km/ ... which of the two friends will return to place P? A. Both B. Boater C. Cyclist D. None of these 

Last Answer : Answer-C Explanation: The cyclist moves both ways at a speed of 12khr so average speed fo the cyclist - 12 km/hr boat sailor moves downstream at 10+4 = 14km/hr and upstream 10- 4 = 6km/hr ... 8.4km/hr The average speed of cyclist is greater .so,cyclist comes first and return to place P.