What is the minimum distance (in metres) required to hear an echo? (1) 10 (2) 13 (3) 17 (4) 21

What is the minimum distance (in metres) required to hear an echo? (1) 10 (2) 13 (3) 17 (4) 21
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Answer :

(3) 17 Explanation: The human ear cannot distinguish echo from the original direct sound if the delay is less than 1/15 of a second. The velocity of sound in dry air is approximately 343 m/s at a temperature of 25⁰C.
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The minimum distance required for an echo to occur is _______. a)30m b)17.2m c)100m d)20m

Description : The minimum distance required for an echo to occur is _______. a)30m b)17.2m c)100m d)20m

Last Answer : b)17.2m

What is the minimum distance between the reflector and the source to hear the echo? ?

Description : What is the minimum distance between the reflector and the source to hear the echo? ?

Last Answer : The minimum distance between the reflector and the source to hear the echo is 18.6 meters.

A bed consists of particles of density 2000 kg/m3 . If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is (A) 25.61 kPa (B) 11.77 kPa (C) 14.86 kPa (D) 21.13 kPa

Description : A bed consists of particles of density 2000 kg/m3 . If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is (A) 25.61 kPa (B) 11.77 kPa (C) 14.86 kPa (D) 21.13 kPa

Last Answer : (B) 11.77 kPa

To hear a clear echo, the distance between the listener and the reflector should be

Description : To hear a clear echo, the distance between the listener and the reflector should be

Last Answer : 17 METER

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50'. What number is missing? -Riddles

Description : 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50'. What number is missing? -Riddles

Last Answer : 22

A beam 3m long simply supported at its ends ,is carrying a point load W at the centre.If the slope at the ends of the beam should not exceed 10,find the deflection at the centre of beam? a.18.41 mm b.13.45 mm c.17.45 mm d.21.67 mm.

Description : A beam 3m long simply supported at its ends ,is carrying a point load W at the centre.If the slope at the ends of the beam should not exceed 10,find the deflection at the centre of beam? a.18.41 mm b.13.45 mm c.17.45 mm d.21.67 mm.

Last Answer : c.17.45 mm

If N is the algebraic difference of grades, S is the minimum sight distance in metres, the length (L) of a summit curve is (A) NS/4 (B) NS²/4 (C) N²S/4(D) (NS)²/4

Description : If N is the algebraic difference of grades, S is the minimum sight distance in metres, the length (L) of a summit curve is (A) NS/4 (B) NS²/4 (C) N²S/4 (D) (NS)²/4

Last Answer : Answer: Option B

If N is the net difference of grades, S is the minimum overtaken sight distance in metres, the length (L) of a summit curve, is (A) NS/4 (B) NS²/4 (C) NS²/4.8 (D) NS²/9.6

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Last Answer : Answer: Option D

A man who makes a profit of 25 percent by selling sugar at Rs. 4.25/kg., lowers his price so as to gain only 5 paise per Kg. In what ratio must his sales be increased so that his total profit may be the same as before? a) 1 : 5 b) 1 : 11 c) 1 : 13 d) 1 : 17 e) 1 : 21

Description : A man who makes a profit of 25 percent by selling sugar at Rs. 4.25/kg., lowers his price so as to gain only 5 paise per Kg. In what ratio must his sales be increased so that his total profit may be the same as before? a) 1 : 5 b) 1 : 11 c) 1 : 13 d) 1 : 17 e) 1 : 21

Last Answer : 125% C.P. of sugar per kg = Rs. 4.25 C.P of the sugar per kg = [4.25×100] / 125 = Rs. 3.40. thus, the profit on 1 kg 85 paise by reducing price to 5 paise, to make same profit he must sell, 85/5 = 17kg so required ratio = 1 : 17. Answer: d)

How long does it take to hear the echo ?

Description : How long does it take to hear the echo ?

Last Answer : Time required to hear the echo is 0.1 sec.

You clap your hands, and instantly you hear an echo of the clap. What does this tell you about the size of the room?

Description : You clap your hands, and instantly you hear an echo of the clap. What does this tell you about the size of the room?

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To hear distinct echo each time interval between original sound and reflected sound must be a)0.2sec b)1sec c)2sec d)0.1sec

Description : To hear distinct echo each time interval between original sound and reflected sound must be a)0.2sec b)1sec c)2sec d)0.1sec

Last Answer : d)0.1sec

An early satellite owned by US Department of Defense that lasted only for 17 days A. Courier B. Echo C. Score D. Westar 1

Description : An early satellite owned by US Department of Defense that lasted only for 17 days A. Courier B. Echo C. Score D. Westar 1

Last Answer : A. Courier

Minimum horsepower of pump required for filling 50m3 water tank, 20 metres high from ground in 30 minutes by lifting water from a well 5 metres below the ground level is a.5.45 KW b.7.5 KW c.6.81 KW d.Tapered bearing e.66.8 KW

Description : Minimum horsepower of pump required for filling 50m3 water tank, 20 metres high from ground in 30 minutes by lifting water from a well 5 metres below the ground level is a.5.45 KW b.7.5 KW c.6.81 KW d.Tapered bearing e.66.8 KW

Last Answer : c. 6.81 KW

f the temperature falls below 18 degrees, the heating is switched on. When the temperature reaches 21 degrees, the heating is switched off. What is the minimum set of test input values to cover all valid equivalence partitions? A. 15, 19 and 25 degrees B. 17, 18, 20 and 21 degrees C. 18, 20 and 22 degrees D. 16 and 26 degrees

Description : f the temperature falls below 18 degrees, the heating is switched on. When the temperature reaches 21 degrees, the heating is switched off. What is the minimum set of test input values to cover all valid equivalence ... 17, 18, 20 and 21 degrees C. 18, 20 and 22 degrees D. 16 and 26 degrees

Last Answer : A. 15, 19 and 25 degrees

The section modulus of a rectangular light beam 25 metres long is 12.500 cm3 . The beam is simply supported at its ends and carries a longitudinal axial tensile load of 10 tonnes in addition to a point load of 4 tonnes at the centre. The maximum stress in the bottom most fibre at the mid span section, is (A) 13.33 kg/cm2 tensile (B) 13.33 kg/cm2 compressive (C) 26.67 kg/cm2 tensile (D) 26.67 kg/cm2 compressive

Description : The section modulus of a rectangular light beam 25 metres long is 12.500 cm3 . The beam is simply supported at its ends and carries a longitudinal axial tensile load of 10 tonnes in addition to a point load of ... 13.33 kg/cm2 compressive (C) 26.67 kg/cm2 tensile (D) 26.67 kg/cm2 compressive

Last Answer : (C) 26.67 kg/cm2 tensile

Minimum compressive strength of cement required at the age of 3 days for ordinary Portland cement of grade 33 is [ A ] 1.15 N/mm2 [ B ] 11.5 N/mm2 [ C ] 2.10 N/mm2 [ D ] 21 N/mm2

Description : Minimum compressive strength of cement required at the age of 3 days for ordinary Portland cement of grade 33 is [ A ] 1.15 N/mm2 [ B ] 11.5 N/mm2 [ C ] 2.10 N/mm2 [ D ] 21 N/mm2

Last Answer : [ B ] 11.5 N/mm2

Minimum number of members required to form a Public Limited Joint Stock Com-pany is (A) 7 (B) 10 (C) 12 (D) 17

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The distance of Venus form the sun as determine by radar echo method is found to be `1.082xx10^(11)m`. The period of its revolution is 224.633 days. I

Description : The distance of Venus form the sun as determine by radar echo method is found to be `1.082xx10^(11)m`. The period of its revolution is 224.633 days. I

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The echo (reflected sounD. will be distinctly heard only at ordinary temperatures if the distance of the reflecting surfaces from the source of sound is at least ----? A. 1120 ft B. 120 ft C. 56 ft (Answer) D. 100 ft E. None of these

Description : The echo (reflected sounD. will be distinctly heard only at ordinary temperatures if the distance of the reflecting surfaces from the source of sound is at least ----? A. 1120 ft B. 120 ft C. 56 ft (Answer) D. 100 ft E. None of these

Last Answer : C. 56 ft (Answer)

An R.C.C. beam of 25 cm width and 50 cm effective depth has a clear span of 6 metres and carries a U.D.L. of 3000 kg/m inclusive of its self weight. If the lever arm constant for the section is 0.865, the maximum intensity of shear stress, is (A) 8.3 kg/cm2 (B) 7.6 kg/cm2 (C) 21.5 kg/cm2 (D) 11.4 kg/cm2

Description : An R.C.C. beam of 25 cm width and 50 cm effective depth has a clear span of 6 metres and carries a U.D.L. of 3000 kg/m inclusive of its self weight. If the lever arm constant for the section is 0.865, the maximum intensity ... , is (A) 8.3 kg/cm2 (B) 7.6 kg/cm2 (C) 21.5 kg/cm2 (D) 11.4 kg/cm2

Last Answer : Answer: Option A

How do i calculate the metres of perimeter for a rectangle with sides 17.5 m by 6.25 m wide?

Description : How do i calculate the metres of perimeter for a rectangle with sides 17.5 m by 6.25 m wide?

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Description : How do i calculate the metres of perimeter for a rectangle with sides 17.5 m long by 3.3 m wide?

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2 pistol were shoot from the same place at an interval of 15 mins and 15 secs but a boy in the train approaching the place hears the second shot 15 mins after the first. The speed of the train(in km/hr),supposing that speed travels at 320 metres per second is. a) 15.166 b) 17.144 c) 18.563 d) 19.188

Description : 2 pistol were shoot from the same place at an interval of 15 mins and 15 secs but a boy in the train approaching the place hears the second shot 15 mins after the first. The speed of the train(in km/hr),supposing that speed travels at 320 metres per second is. a) 15.166 b) 17.144 c) 18.563 d) 19.188

Last Answer : D Let the speed of the train be x m/sec Then distance travelled by the train in 15mins = distance travelled by sound in 15secs X*15*60 = 320*15 900x = 4800 X=4800/900 X=5.33 Speed of the train 5.33 m/s Convert m/s into km/hr 5.33m =(5.33*18/5) =(95.94/5) =19.188 km/hr

Sakthi running at 27 kmph alongside a railway track in 272 metres ahead of the engine of a 240 metres long train running at 135 kmph in the same direction. In how much time will the train pass sakthi? A) 24 B) 29 C) 36 D) 17

Description :  Sakthi running at 27 kmph alongside a railway track in 272 metres ahead of the engine of a 240 metres long train running at 135 kmph in the same direction. In how much time will the train pass sakthi? A) 24 B) 29 C) 36 D) 17

Last Answer : ANSWER:D  Explanation:  Speed of the train = 135 kmph  Speed of sakthi = 27 kmph  Speed of train relative to sakthi = (135-27) kmph  =108 kmph  We have to find the time in seconds, so convert ... of the train = Distance / Time  Therefore Time taken = ( 512 / 30) sec  = 17 sec

The Shopkeeper increased the price of a product by 75% so that customer finds it difficult to purchase the required amount. But somehow the customer managed to purchase only 140% of the required amount. What is the net difference in the expenditure on that product? a) 12.5 b) 26.0 c) 13.5 d) 17.5 e) 19.8

Description : The Shopkeeper increased the price of a product by 75% so that customer finds it difficult to purchase the required amount. But somehow the customer managed to purchase only 140% of the required amount. What is the net difference in the ... on that product? a) 12.5 b) 26.0 c) 13.5 d) 17.5 e) 19.8

Last Answer : Answer: D  Quantity×Rate=Price  1x1=1  1.4x1.75=2.45  Decrease in price = (0.175/1) × 100  = 17.5%

A three hinged arch is loaded with an isolated load 1000 kg at a horizontal distance of 2.5 m from the crown, 1 m above the level of hinges at the supports 10 metres apart. The horizontal thrust is (A) 1250 kg (B) 125 kg (C) 750 kg (D) 2500 kg

Description : A three hinged arch is loaded with an isolated load 1000 kg at a horizontal distance of 2.5 m from the crown, 1 m above the level of hinges at the supports 10 metres apart. The horizontal thrust is (A) 1250 kg (B) 125 kg (C) 750 kg (D) 2500 kg

Last Answer : (A) 1250 kg

Starting from point A, Ajit walks 14 metres towards west, he then turns to his right and walks 14 metres and then turns to his left and walks 10 metres. He again turns to his left and walks 14 metres and reaches to the point E. The shortest distance between A and E is (A) 38 (B) 42 (C) 52 (D) 24

Description : Starting from point A, Ajit walks 14 metres towards west, he then turns to his right and walks 14 metres and then turns to his left and walks 10 metres. He again turns to his left and walks 14 metres and reaches to the point E. The shortest distance between A and E is (A) 38 (B) 42 (C) 52 (D) 24

Last Answer : Answer: D

What is Echo ?

Description : What is Echo ?

Last Answer : When a word separates from the original and repeats the original word , the reflected word is called an echo.

Which phenomenon is responsible for the echo of sound wave? (1) Reflection (2) Refraction (3) Interference (4) Polarization

Description : Which phenomenon is responsible for the echo of sound wave? (1) Reflection (2) Refraction (3) Interference (4) Polarization

Last Answer : (1) Reflection Explanation: Reflection of sound waves off of surfaces lead to one of two phenomena - an echo or a reverberation. The echo is produced due to hitting of the sound waves with the ... reflected sound wave reaches the ear more than 0.1 seconds after the original sound wave was heard.

Which phenomenon is responsible for the echo of sound wave? (1) Reflection (2) Refraction (3) Interference (4) Polarisation

Description : Which phenomenon is responsible for the echo of sound wave? (1) Reflection (2) Refraction (3) Interference (4) Polarisation

Last Answer : Reflection

An intermediate T-beam reinforced with two layers of tensile steel with clear cover 13 cm encasted with the floor of a hall 12 metres by 7 metres, is spaced at 3 metres from adjoining beams and if the width of the beam is 20 cm, the breadth of the flange is (A) 300 cm (B) 233 cm (C) 176 cm (D) 236 cm

Description : An intermediate T-beam reinforced with two layers of tensile steel with clear cover 13 cm encasted with the floor of a hall 12 metres by 7 metres, is spaced at 3 metres from adjoining beams and if the width of the beam is ... breadth of the flange is (A) 300 cm (B) 233 cm (C) 176 cm (D) 236 cm

Last Answer : Answer: Option C

Electric field strength on a dust particle having charge equal to 8 × 10- 19 when plates are separated by distance of 2 cm and have a potential difference of 5 kV is A. 2.0 × 10-13 NB. 3 NC. 5 ND. 20 N

Description : Electric field strength on a dust particle having charge equal to 8 × 10- 19 when plates are separated by distance of 2 cm and have a potential difference of 5 kV is A. 2.0 × 10-13 N B. 3 N C. 5 N D. 20 N

Last Answer : 2.0 × 10-13 N

Pick up the correct statement from the following: (A) Minimum desirable width of medians on rural highways is 5 metres (B) Minimum width of medians should be 3 metres (C) On long bridges and viaducts, the width of medians should be 1.5 m (D) All the above

Description : Pick up the correct statement from the following: (A) Minimum desirable width of medians on rural highways is 5 metres (B) Minimum width of medians should be 3 metres (C) On long bridges and viaducts, the width of medians should be 1.5 m (D) All the above

Last Answer : Answer: Option D

For design of sewers for sullage, minimum velocity of ---- metres per second is taken. (a) 1.0 m sec* (b) 1.5 m/sec (c) 2.0 m/sec (d) 2.5 m/sec

Description : eFor design of sewers for sullage, minimum velocity of ---- metres per second is taken. (a) 1.0 m sec* (b) 1.5 m/sec (c) 2.0 m/sec (d) 2.5 m/sec

Last Answer : (a) 1.0 m sec*

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Description : The piston of a steam engine moves in S.H.M. The crank rotates at 180 r.p.m. and the stroke length is 2 metres. The linear velocity of the piston when it is at a distance of 1 metre from the centre is a.8.88 m/sec b.16.32 m/sec c.5.88 m/sec d.8.16 m/sec e.Zero

Last Answer : e. Zero

Noise emitted by a ventilation fan at a distance of 3 metres is about __________ decibels. (A) 85 (B) 105 (C) 125 (D) 145

Description : Noise emitted by a ventilation fan at a distance of 3 metres is about __________ decibels. (A) 85 (B) 105 (C) 125 (D) 145

Last Answer : (B) 105

Noise level heard at a distance of about 100 metres from a jet engine with after burner is about __________ decibels. (A) 120 (B) 140 (C) 170 (D) 200

Description : Noise level heard at a distance of about 100 metres from a jet engine with after burner is about __________ decibels. (A) 120 (B) 140 (C) 170 (D) 200

Last Answer : (C) 170

Sound produced by an automobile horn heard at a distance of 1.5 metres corresponds to about __________ decibels. (A) 90 (B) 120 (C) 150 (D) 180

Description : Sound produced by an automobile horn heard at a distance of 1.5 metres corresponds to about __________ decibels. (A) 90 (B) 120 (C) 150 (D) 180

Last Answer : (B) 120

As per international norms, the maximum permissible value of noise level in the industrial environment is __________ decibels as measured at a distance of 1.5 metres from the source of noise. (A) 110 (B) 85 (C) 60 (D) 45

Description : As per international norms, the maximum permissible value of noise level in the industrial environment is __________ decibels as measured at a distance of 1.5 metres from the source of noise. (A) 110 (B) 85 (C) 60 (D) 45

Last Answer : (B) 85

If the length of a combined footing for two columns l metres apart is L and the projection on the left side of the exterior column is x, then the projection y on the right side of the exterior column, in order to have a uniformly distributed load, is (where is the distance of centre of gravity of column loads). (A) y = L - (l - ) (B) y = L/2 + (l - ) (C) y = L/2 - (l + ) (D) y = L/2 - (l - )

Description : If the length of a combined footing for two columns l metres apart is L and the projection on the left side of the exterior column is x, then the projection y on the right side of the exterior column, in order to have a uniformly distributed ... l - ) (C) y = L/2 - (l + ) (D) y = L/2 - (l - )

Last Answer : Answer: Option D

If metres is the distance between extreme axles of a vehicle, its gross load should not exceed (A) 1525 (L + 4.3) - 14.7 L2 (B) 1526 (L + 5.3) - 14.7 L2 (C) 1525 (L + 6.3) - 14.7 L2 (D) 1525 (L + 7.3) - 14.7 L2

Description : If metres is the distance between extreme axles of a vehicle, its gross load should not exceed (A) 1525 (L + 4.3) - 14.7 L2 (B) 1526 (L + 5.3) - 14.7 L2 (C) 1525 (L + 6.3) - 14.7 L2 (D) 1525 (L + 7.3) - 14.7 L2

Last Answer : Answer: Option D

If L is the length of vehicles in metres, C is the clear distance between two consecutive vehicles (stopping sight distance), V is the speed of vehicles in km/hour, the maximum number N of vehicles/hour, is (A) N = 1000 V / (L + C) (B) N = (L + C) / 1000 V (C) N = 1000 L / (C + V) (D) N = 1000 C / (L + V)

Description : If L is the length of vehicles in metres, C is the clear distance between two consecutive vehicles (stopping sight distance), V is the speed of vehicles in km/hour, the maximum number N of vehicles/hour, is (A) N = 1000 V / (L + C ... ) / 1000 V (C) N = 1000 L / (C + V) (D) N = 1000 C / (L + V)

Last Answer : Answer: Option A

If N is the algebraic difference of grades, S is the head light beam distance in metres, the length (L) of a valley curve, is (A) NS²/4 (B) NS²/6 (C) NS²/9.6 (D) NS²/4.8

Description : If N is the algebraic difference of grades, S is the head light beam distance in metres, the length (L) of a valley curve, is (A) NS²/4 (B) NS²/6 (C) NS²/9.6 (D) NS²/4.8

Last Answer : Answer: Option A

If the velocity of moving vehicles on a road is 24 km/per hour, stopping distance is 19 metres and average length of vehicles is 6 metres, the basic capacity of lane, is (A) 500 vehicles per hour (B) 700 vehicles per hour (C) 1000 vehicles per hour (D) 1250 vehicles per hour

Description : If the velocity of moving vehicles on a road is 24 km/per hour, stopping distance is 19 metres and average length of vehicles is 6 metres, the basic capacity of lane, is (A) 500 vehicles per hour (B) 700 vehicles per hour (C) 1000 vehicles per hour (D) 1250 vehicles per hour

Last Answer : Answer: Option C

If C is basic capacity per lane, V is velocity in km/hour, S is stopping distance plus length of the vehicles in metres, the formula C = 1000V/S is applicable to (A) District roads (B) Two lane roads (C) Two lane roads in one direction (D) None of these

Description : If C is basic capacity per lane, V is velocity in km/hour, S is stopping distance plus length of the vehicles in metres, the formula C = 1000V/S is applicable to (A) District roads (B) Two lane roads (C) Two lane roads in one direction (D) None of these

Last Answer : Answer: Option C

If h and h1 are the heights of a light house and the observer in a ship in metres above M S L then the horizontal distance from the ship to the light house in kilometres is (A) h + h1) (B) h - h1) (C) h × h1) (D) 3.86 h + h1)

Description : If h and h1 are the heights of a light house and the observer in a ship in metres above M S L then the horizontal distance from the ship to the light house in kilometres is (A) h + h1) (B) h - h1) (C) h × h1) (D) 3.86 h + h1)

Last Answer : (A) h + h1)

If F is the fetch, the straight line distance of open water available in kilometres, the height of the wave in metres is (A) 0.15 (B) 0.20 (C) 0.28 (D) 0.34

Description : If F is the fetch, the straight line distance of open water available in kilometres, the height of the wave in metres is (A) 0.15 (B) 0.20 (C) 0.28 (D) 0.34

Last Answer : (D) 0.34