Question
Number. 51. What atmospheric conditions will cause the true landing
speed of an aircraft to be highest?.
Option A.
Low temp, high humidity.
Option B.
Head wind, low humidity.
Option C.
High temp, high humidity.
Correct
Answer is. High temp, high humidity.
Explanation.
Lift is least at low density. Density is lowest at high temperature
and high humidity.
Question
Number. 52. Structures designed to withstand compression are called
a.
Option A.
tie.
Option B.
strut.
Option C.
beam.
Correct
Answer is. strut.
Explanation.
Tension - Tie, Compression - Strut, Bending - Beam.
Question
Number. 53. 1 Pascal equals.
Option
A. 105 N/m2.
Option
B. 1 N/m2.
Option C.
10 Nm.
Correct
Answer is. 1 N/m2.
Explanation.
1 Pa = 1 N/m2.
Question
Number. 54. The addition of 2 different vectors to produce another
vector is called.
Option A.
component.
Option B.
resolution.
Option C.
resultant.
Correct
Answer is. resultant.
Explanation.
The resultant of two vectors. The mathematical process is actually
called 'composition'.
Question
Number. 55. Two items weighing 11kg and 8kg are placed 2m and 1m
respectively aft of the C of G of an aircraft. How far forward of the
C of G must a weight of 30kg be placed so as not to change the C of
G?.
Option A.
2m.
Option B.
1.5m.
Option C.
1m.
Correct
Answer is. 1m.
Explanation.
Total moment = (11*2) + (8*1) = 30kgm. The 30 kg mass must be placed
such that 30kg * Xm = 30 kg m. Hence X = 1m.
Question
Number. 56. A point at which the total force of a body acts is known
as the.
Option A.
centre of gravity.
Option B.
point of equilibrium.
Option C.
centre of mass.
Correct
Answer is. centre of gravity.
Explanation.
If by force they mean 'weight' then it is Centre of Gravity.
Question
Number. 57. A load of 600N is suspended by a cable. If the stress in
the cable is said to be limited to 15N/mm2 the
minimum cross sectional area of the cable must be.
Option
A. 0.025mm2.
Option
B. 9000mm2.
Option
C. 40mm2.
Correct
Answer is. 40mm2.
Explanation.
Stress = Force/Area. Area = Force/Stress = 600/15 = 40mm2.
Question
Number. 58. A spring, operating within its elastic range, shortens by
60mm when a load of 480N is applied to it. Calculate the total
shortening when the load is increased by 120N.
Option A.
82mm.
Option B.
45mm.
Option C.
75mm.
Correct
Answer is. 75mm.
Explanation.
600/480 * 60 = 75mm.
Question
Number. 59. The c.g. of a triangular plate is at the intersection of.
Option A.
medians from a vertex to the opposite side.
Option B.
angle bisectors.
Option C.
perpendicular bisectors.
Correct
Answer is. medians from a vertex to the opposite side.
Explanation.
NIL.
Question
Number. 60. When a square block of material is pushed into a
parallelogram, the material is under what stress type?.
Option A.
Compression.
Option B.
Torsion.
Option C.
Shear.
Correct
Answer is. Shear.
Explanation.
NIL.
http://groups.physics.umn.edu/demo/old_page/demo_gifs/1R30_20.GIF
Question
Number. 61. A quantity which has size but no direction is called a.
Option A.
Scalar.
Option B.
Moment.
Option C.
Vector.
Correct
Answer is. Scalar.
Explanation.
scalar has size only (mass, area etc.). A vector has size and
direction (velocity, force etc.).
Question
Number. 62. The advantage of using a machine is.
Option A.
mechanical advantage of input.
Option B.
mechanical advantage of output.
Option C.
input work is less than the output work.
Correct
Answer is. mechanical advantage of output.
Explanation.
Mechanical advantage is usually on the outp.
Question
Number. 63. Which of the following can transmit pressure?.
Option A.
Liquids and gases.
Option B.
Solids and gases.
Option C.
Any matter can transmit pressure, depending on temperature.
Correct
Answer is. Liquids and gases.
Explanation.
NIL.
Question
Number. 64. A moment is created by a force of 5N acting 4m from the
pivot on a uniform bar. At what distance must a force of 10N be
applied to balance the beam?.
Option A.
8 m.
Option B.
4 m.
Option C.
2 m.
Correct
Answer is. 2 m.
Explanation.
5 * 4 = 20, 10 * X = 20 X = 2m.
Question
Number. 65. A lever of length 105 cm is used with a fulcrum placed 15
cm from the end bearing the load. Its mechanical advantage is.
Option A.
1/6.
Option B.
7.
Option C.
6.
Correct
Answer is. 6.
Explanation.
The TOTAL length is 105 cm, so the input end is 90 cms. 90/15 = 6.
Question
Number. 66. The stress created when a material is pulled apart is
called.
Option A.
tension.
Option B.
torsion.
Option C.
compression.
Correct
Answer is. tension.
Explanation.
NIL.
Question
Number. 67. The yield point of a material is the point at which.
Option A.
strain becomes proportional to stress.
Option B.
the material ruptures or breaks.
Option C.
permanent deformation takes place.
Correct
Answer is. permanent deformation takes place.
Explanation.
NIL.
Question
Number. 68. Assuming constant temperature. If a steel bar of length 2
m deforms to a length of 2.2 m under applied load. The strain is.
Option A.
1.1.
Option B.
0.9.
Option C.
0.1.
Correct
Answer is. 0.1.
Explanation.
Strain = Extension/Original Length = 0.2/2 = 0.1.
Question
Number. 69. A Scalar quantity has.
Option A.
sense, magnitude and direction.
Option B.
sense and direction.
Option C.
magnitude only.
Correct
Answer is. magnitude only.
Explanation.
NIL.
Question
Number. 70. A hydraulic piston of 2.5 square inches produces 7500lbf,
What pressure is used?.
Option A.
5000 PSI.
Option B.
3000 PSI.
Option C.
7000 PSI.
Correct
Answer is. 3000 PSI.
Explanation.
Pressure = Force/Area.
Question
Number. 71. Forces passing through a common point are said to be.
Option A.
coherent.
Option B.
coplanar.
Option C.
concurrent.
Correct
Answer is. concurrent.
Explanation.
NIL.
Question
Number. 72. A force of 5 Newtons acting perpendicularly at 300
centimetres from the pivot produces a moment of.
Option A.
1500 Newton metre.
Option B.
15 Newton metre.
Option C.
1.5 Kilonewton millimetre.
Correct
Answer is. 15 Newton metre.
Explanation.
3m * 5N = 15 Nm.
Question
Number. 73. Equilibrium of translation occurs when.
Option A.
downward forces equal upward (reactive) forces.
Option B.
clockwise moments equal counterclockwise moments.
Option C.
clockwise forces and counterclockwise forces are equal.
Correct
Answer is. downward forces equal upward (reactive) forces.
Explanation.
Translation is linear movement.
Question
Number. 74. The conversion factor to convert litres to pints is.
Option A.
0.57.
Option B.
1.76.
Option C.
2.2.
Correct
Answer is. 1.76.
Explanation.
NIL. http://www.thetipsbank.com/convert.htm
Question
Number. 75. Hydraulic pressure can be restored by.
Option A.
the use of pressure/heat exchange.
Option B.
compressing the air charge in an accumulator.
Option C.
compressing the fluid in a reservoir.
Correct
Answer is. compressing the air charge in an accumulator.
Explanation.
NIL.
Question
Number. 76. When checking a hydraulic accumulator initial air
pressure, the hydraulic system pressure.
Option A.
should be at the normal working pressure.
Option B.
is not important.
Option C.
should be released.
Correct
Answer is. should be released.
Explanation.
NIL.
Question
Number. 77. One kg is the mass of.
Option A.
one litre of pure water.
Option B.
one pint of pure water.
Option C.
one gallon of pure water.
Correct
Answer is. one litre of pure water.
Explanation.
NIL. http://www.bartleby.com/68/85/3685.html
Question
Number. 78. The centre of gravity of a triangle is.
Option A.
1/3 the median from the base.
Option B.
1/3 the bisector from the base.
Option C.
1/3 the height from the base.
Correct
Answer is. 1/3 the median from the base.
Explanation.
http://en.wikipedia.org/wiki/Triangle
Question
Number. 79. A lifting machine moves with an effort, a distance of 200
cm, in order to raise it 0.5 m. The Velocity Ratio is.
Option A.
0.25.
Option B.
4.
Option C.
40.
Correct
Answer is. 4.
Explanation.
Distance ratio input/ output = 2/0.5 = 4. Velocity ratio is same as
Distance ration.
Question
Number. 80. Two Vectors are at 90 degrees to each other having
magnitudes of 3N and 4N. The resultant is.
Option A.
5N.
Option B.
1N.
Option C.
7N.
Correct
Answer is. 5N.
Explanation.
Vectors make a 3-4-5 triangle.
Question
Number. 81. Which of the following has no units?.
Option A.
Strain.
Option B.
Stress.
Option C.
Elasticity.
Correct
Answer is. Strain.
Explanation.
NIL.
2.2.
Mechanics – Kinetics.
Question
Number. 1. For a car weighing 1000 N, what force would be required to
accelerate the car to 3 ms-2.
Option A.
3270 N.
Option B.
305.8 N.
Option C.
3000 N.
Correct
Answer is. 305.8 N.
Explanation.
F = ma F = 1000/9.81 * 3 F = 305.8 N (The 'divide by' 9.81 is
necessary to convert the 1000 N into a mass (in kg)).
Question
Number. 2. A time period of 10 microseconds is equal to a frequency
of.
Option A.
100 kHz.
Option B.
10 kHz.
Option C.
1 Mhz.
Correct
Answer is. 100 kHz.
Explanation.
Frequency = 1/time period. 1/0.00001 = 100,000 = 100 kHz.
Question
Number. 3. The SI unit of acceleration is the.
Option
A. metre per second squared (m/s2).
Option B.
metre per second (m/s).
Option
C. square metre (m2).
Correct
Answer is. metre per second squared (m/s2).
Explanation.
NIL.
Question
Number. 4. If a body starts at rest and reaches 84 m/s in 3 seconds,
its acceleration is.
Option
A. 28 m/s2.
Option
B. 14 m/s2.
Option
C. 252 m/s2.
Correct
Answer is. 28 m/s2.
Explanation.
Acceleration = change in speed / time.
Question
Number. 5. The SI unit of velocity is the.
Option
A. metre per second squared (m/s2).
Option B.
metre per second (m/s).
Option C.
metre (m).
Correct
Answer is. metre per second (m/s).
Explanation.
NIL.
Question
Number. 6. An aircraft flies 1350 nmiles in 2h 15mins. What is the
average speed?.
Option A.
600 nmiles/hour.
Option B.
600 miles/hour.
Option C.
150 nmiles/hour.
Correct
Answer is. 600 nmiles/hour.
Explanation.
Average speed = distance/time = 1350/2.25 = 600 nm/h.
Question
Number. 7. A spring extends 7 cm to the ground and back again 20
times a minute. What is the period?.
Option A.
7 cm.
Option B.
3 seconds.
Option C.
1/3 cycle.
Correct
Answer is. 3 seconds.
Explanation.
Frequency = 20/60 = 1/3 Hz. Time period = 1/f = 3 seconds.
Question
Number. 8. A cyclist goes from rest to 50 m/s in 5 seconds. What is
the average acceleration?.
Option
A. 10 m/s2.
Option
B. 12 m/s2.
Option
C. 8 m/s2.
Correct
Answer is. 10 m/s2.
Explanation.
Acceleration = change in speed / time.
Question
Number. 9. What is the period of a frequency of 4 Hz?.
Option A.
8 seconds.
Option B.
0.25 seconds.
Option C.
4 seconds.
Correct
Answer is. 0.25 seconds.
Explanation.
Period = 1/f.
Question
Number. 10. A dot rotates around the circumference of a circle. If
the vertical position of this dot is plotted on a graph with respect
to time the result will be.
Option A.
a linear motion.
Option B.
a transverse waveform.
Option C.
a sinusoidal waveform.
Correct
Answer is. a sinusoidal waveform.
Explanation.
This is why an AC generator produces a sine wave frequency.
Question
Number. 11. A freely falling body, falling from a height of 2km, and
assuming g = 10m/s2,
will strike the ground in a time of.
Option A.
400s.
Option B.
80s.
Option C.
20s.
Correct
Answer is. 20s.
Explanation.
From the equations of motion s = ut + 1/2at2.
If it starts at rest u (and hence ut) is zero. Use s = 2000 m, plug
in the numbers and transpose for t.
Question
Number. 12. What is the angular velocity of a shaft rotating at
300rpm in radians/second?.
Option A.
10π radians/second.
Option B.
2π radians/second.
Option C.
5π radians/second.
Correct
Answer is. 10π radians/second.
Explanation.
velocity = 2π(RPM)/60 = 2π * 300/60 = 10π radians/second.
Question
Number. 13. The force that acts on a body to cause it to rotate in a
circular path is called the.
Option A.
centripetal force.
Option B.
centrifugal force.
Option C.
inertia force.
Correct
Answer is. centripetal force.
Explanation.
Centripetal' force is the force pulling the rotating object towards
the centre of rotation. 'Centrifugal' force is the equal and opposite
reaction.
Question
Number. 14. An aircraft of 2 metric tonnes uses 800 kilojoules
kinetic energy to make an emergency stop. Its brakes apply a force of
10 kiloNewtons. What distance does it travel before it comes to a
stop?.
Option A.
40m.
Option B.
800m.
Option C.
80m.
Correct
Answer is. 80m.
Explanation.
Energy = Force * Distance. 800,000J = 10,000N x Distance. Distance =
??.
Question
Number. 15. A body rotating at an angular velocity of 5 radians/sec,
with a radius of 5 metres has a speed of.
Option A.
5π metres per second.
Option B.
5 metres per second.
Option C.
25 metres per second.
Correct
Answer is. 25 metres per second.
Explanation.
velocity = Radius * Omega (Omega = radians/sec). V = 5 * 5 = 25 m/s.
Question
Number. 16. A mass of 400 kg moves 27metres, with a force of 54N,
what is the work produced?.
Option A.
1458 J.
Option B.
583.2 KJ.
Option C.
10.1 KJ.
Correct
Answer is. 1458 J.
Explanation.
Work = Force x Distance = 54 * 27 = 1458 J. It is not moving under
gravity so the 400 kg is a red herring.
Question
Number. 17. A mass on a spring nearly hits the ground 20 times a
minute, its frequency is.
Option A.
3 cycles per second.
Option B.
1/3 cycle per second.
Option C.
20 cycles per second.
Correct
Answer is. 1/3 cycle per second.
Explanation.
cycles per minute = 20/60 cycles per second = 2/6 = 1/3 cycle per
second.
Question
Number. 18. A body travelling at 20 m/s accelerates to 36 m/s in 8
seconds, what is its acceleration?.
Option
A. 8 m/s2.
Option
B. 4 m/s2.
Option
C. 2 m/s2.
Correct
Answer is. 2 m/s2.
Explanation.
V = u +at 36 = 20 + 8a 36-20 = 8a 16/8 = a.
Question
Number. 19. A body dropped from 10 m will hit the ground in.
Option A.
2 seconds.
Option B.
0.2 seconds.
Option C.
1.41 second.
Correct
Answer is. 1.41 second.
Explanation.
s = ut + 1/2at2.
Take s = 10, u = 0, a = g = 10. Calculate t. (Remember that 0 * t =
0).
Question
Number. 20. What is the rate of gravity?.
Option
A. 12.7 m/s2.
Option
B. 0.981 m/s2.
Option
C. 9.81 m/s2.
Correct
Answer is. 9.81 m/s2.
Explanation.
Gravity = 9.81 m/s2.
Question
Number. 21. An object travels 18 km in 1 minute 30 seconds. What is
its average speed?.
Option A.
200 m/s.
Option B.
270 m/s.
Option C.
100 ms.
Correct
Answer is. 200 m/s.
Explanation.
Average speed = distance/time = 18000 metres / 90 seconds = 200 m/s.
Question
Number. 22. 100 m is approximately.
Option A.
220 yards.
Option B.
109 yards.
Option C.
66 yards.
Correct
Answer is. 109 yards.
Explanation.
m = 3.3 ft. 100 m = 330 ft. 3 ft = 1 yd so 330/3 = 110 yards.
Question
Number. 23. A car moves over a distance of 5 miles at steady speed in
10 minutes. What is the speed?.
Option A.
30 mph.
Option B.
15 mph.
Option C.
60 mph.
Correct
Answer is. 30 mph.
Explanation.
in 10 mins, 10 miles in 20 mins, 15 miles in 30 mins, 30 miles in 1
hr.
Question
Number. 24. A spaceship travels a distance of 480,000 miles in 2
days. What is its speed?.
Option A.
48,000 mph.
Option B.
36,000 mph.
Option C.
10,000 mph.
Correct
Answer is. 10,000 mph.
Explanation.
480,000/48 = 10,000 MPH.
Question
Number. 25. A cyclist covers a distance of 1,000 m at a constant
speed in 90 seconds, What is his speed?.
Option A.
50 m/s.
Option B.
12.5 m/s.
Option C.
11.1 m/s.
Correct
Answer is. 11.1 m/s.
Explanation.
1000m/90secs = 11.1 m/s
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