WorksheetsLHTB Physics Pre-Exam (2.2 Mechanics – Statics)
Total questions: 81
Worksheet time: 41mins
An insulator has its electrons
tightly bound
loosely bound
totally free from electrons
The centre of gravity of an aircraft is adjusted by two weights, 10 kg and 5 ckg plaed 4m and 2 m aft of the c of g. To what position must a 20 kg weight be added to balance the c of g?
2.5m
4m
2m
For the CGS system, the force is...
the 'dyne' which produces an acceleration of 1cm/ s2 for a mass of gram
the 'pd1' which produces an acceleration of 1 cm/s2 for a mass of gram.
the 'N' which produces an acceration of 1 cm/s2 for a mass of gram.
The quadrature component of a vector is...
90 degrees to the original
180 degrees to the original
45 degrees to the original
1 Newton is equal to
1 kilogram meter per second per second
1 kilogram of force
1 joule per second
The SI unit of mass is the
kg
lb
slug
slug is a unit of…
speed
mass
weight
If an object in air is submerged in a liquid or a gas its weight will…
increase
decrease
remain the same
If a material is loaded excessively and is permanently deformed, it is said to be...
strained
stressed
stretched
The SI unit of force is the…
Newton
Metre
Pascal
The formula for calculating stress is…
load divided by cross sectional area
area divided by load
load multiplied by cross sectional area
Stress is given by
Force per unit area
Extension per original length
Force per original length
The force which opposes twisting deformation is
Torsion
Strain
Shear
A force perpendicular to a beam produces what type of stress
Shear
Tensile
Compressive
The extension of the spring can be determined using
Charles law
Newton's second law
Hooke's law
When is steel bar is over stressed what is the name of the point at which it does not return to its original form after the load is released?
Yield point
Ultimate point
Young's modulus
Two couples with magnitude F act against each other the resultant will be
-2F
2F
0
The height of mercury required to give one bar is
700 mm
1000 mm
760mm
A vessel has 25 ml of water which produces 10 kilopascals, if another 125ml of water is added what will the pressure be in the vessel?
40kPa
50kPa
60kPa
Two hydraulic jacks with different diameters have the same fluid pressures entering at the same rate. They will extend at.
different rates
same rate
the same rate until the smaller jack becomes full
What load can be lifted on jack B? (expl:10 times the area, then it can lift 10 times the load)
300N
200N
100N
The most common method of expressing pressure is in
inches
pounds per square inch
grams per square inch
The difference between two pressures is
differential pressure
vacuum pressure
static pressure
What torque loading would you apply to a nut if the force is 50 lbs, exerted 2 feet from its axis?(Expl: Torque loading = force * distance)
100 lbs.ft
200 lbs.ft
300 lbs.ft
In a jack with a ram only on one side and hydraulic fluid applied from both sides
the ram will move opposite to the side where the ram is due to pressure acting on differential areas
the ram will move to the side where the ram is, due to pressure acting on differential areas
a condition of hydraulic lock exists and no movement will take place
Using the same hydraulic pressure, the force applied by a hydraulic jack of 4 sq. inch piston area
will be equal to that applied by a similar jack of 2 sq. inch piston area
will be twice that applied by a similar jack of 2 sq. inch piston area
will be half that applied by a similar jack of 2 sq. inch piston area
A pressure of 100 PSI acts on two jacks in a hydraulic system, having piston areas 2 sq in and 4 sq in
the smaller jack will exert a force of 200 lb and the larger a force of 400 lb
A. the smaller jack will exert a force of 50 lb and the larger a force of 25 lb
the two jacks will exert the same force
The purpose of an accumulator in a hydraulic system is to
store hydraulic fluid under pressure
relieve excess pressure
collect air from the hydraulic fluid, thus reducing the requirement for frequent bleeding
If the hydraulic system accumulator has a low air pressure, it will cause
rapid pressure fluctuations during operation of services
slow build up of pressure in the system
rapid movement of the operating jacks
The specific torque loading for a bolt is 50 lbs.ins but an extension of 2 inches is needed to reach the bolt in addition to the 8 inches torque wrench. What will the actual reading?
(Expl: New torque reading = desired torque x L/(x+L))
54 lb.ins
40 lb.ins
60 lb.ins
If 1500 psi hydraulic pressure is pumped into an accumulator, with a pre-charge air pressure of 1000 psi the gauge will read.
2500 psi
1500 psi
1000 psi
Young's modulus is...
stress * stain
stress / strain
strain / stress
A cylinder filled with water to half a metre will exert a pressure of…(Expl:Pressure = density gravity height)
4900Pa
49Pa
4.9Pa
A mass of 10kg placed 2 metres away from a pivot will have a moment of...(Expl: Moment = force * radius)
196 NM
50 NM
20 NM
25 litres of fuel exerts a pressure of 10KPa. If a further 125 litres is added, the pressure will now be.
50kPa
60kPa
40kPa
1000 lb/in2 is in an accumulator. If 3000 lb/in2 of hydraulic fluid is pumped in, what is the pressure on the air side?
3000 lb/in2
4000lb/in2
2000lb/in2
A fractional decrease in volume of a material when it is compressed is a function of the…
compressive strain
pressured strain
bulk modulus
A ram has a piston with 2 in2. Another ram with a piston of 4 in2 will provide.
the same force
double the force
square of the force
How much force is exerted by piston if it is subjected to a pressure of 3000 Pa and has surface area of 2.5 m2?
(Expl: Force = pressure * area)
7500N
3000N
1200N
A force of 10 million Newton’s is expressed numerically as...
10MN
1MN
100MN
A millilitre is equal to
one thousandth of a litre
one millionth of a litre
one million litres
If a square has an area of 9m2, one side is…
3m
3 sq.m
3m^2
A vector quantity is a quantity which…
Possesses direction only
Possesses sense only
Possesses sense, magnitude and direction
One atmosphere is equal to…
14.7 lbf/in^2
28.9 inches of Hg
1.2kg/m^2
Strain is calculated by..
Extension ÷ Original Length
Original Length * Extension
Original Length * Extension^2
When a twisting force is applied to a bolt, what stress is exerted on to the head?
Torsion
Compressive
Shear
When you overstress a steel bar, what is the point called where it does not return to its original form?
Plastic limit
Deformation limit
Elasticity limit
The formula for calculating shear is
force ÷ area parallel to the force
force * area
force ÷ cross-sectional area
A force 10 N is placed 2 Meters from a pivot point, what is the moment?
20NM
40NM
80NM
If a tensile load is placed on a bar, it will...
stretch
bend
crush
What atmospheric conditions will cause the true landing speed of an aircraft to be highest?
High temp, high humidity
High temp, low humidity
Low temp, low humidity
Structures designed to withstand compression are called a…
Strut
Tie
Beam
1 Pascal equals
1 N/m2
10NM
10N/m2
The addition of 2 different vectors to produce another vector is called…
Resultant
Resolution
Component
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?
2m
1m
1.5m
A point at which the total force of a body acts is known as the...
Centre of gravity
Centre of mass
point of equilibrium
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...
200mm^2
40mm^2
0.025mm^2
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.
75mm
85mm
45mm
The c.g. of a triangular plate is at the intersection of...
medians from a vertex to the opposite side.
perpendicular bisectors.
angle bisectors.
When a square block of material is pushed into a parallelogram, the material is under what stress type?
shear
compression
torsion
A quantity which has size but no direction is called a...
Scalar
Moment
Vector
The advantage of using a machine is
mechanical advantage of output
input work is less than the output work
mechanical advantage of input
Which of the following can transmit pressure?
Any matter can transmit pressure depending on the temperature
Solids
Liquids and gases
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?
8m
4m
2m
A lever of length 105 cm is used with a fulcrum placed 15 cm from the end bearing the load. Its mechanical advantage is...
1/6
7
6
The stress created when a material is pulled apart is called...
tension
compression
torsion
The yield point of a material is the point at which...
permanent deformation takes place
the material ruptures or breaks
strain becomes proportional to stress
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...
1.1
1.9
0.1
A Scalar quantity has…
sense, magnitude and direction
sense and direction
magnitude only
A hydraulic piston of 2.5 square inches produces 7500lbf, What pressure is used?
7000PSI
5000PSI
3000PSI
Forces passing through a common point are said to be...
concurrent
coplanar
coherent
A force of 5 Newtons acting perpendicularly at 300 centimetres from the pivot produces a moment of...
15 Newton metre
1500 Newton metre
1.5 Newton millimetre
Equilibrium of translation occurs when...
clockwise forces and counterclockwise forces are equal.
clockwise moments equal counterclockwise moments.
downward forces equal upward (reactive) force
The conversion factor to convert litres to pints is...
0.57
2.2
1.76
Hydraulic pressure can be restored by..
compressing the fluid in a reservoir
compressing the air charge in an accumulator
the use of pressure/heat exchange
When checking a hydraulic accumulator initial air pressure, the hydraulic system pressure...
should be released
should be at normal working pressure
is not important
One kg is the mass of is…
one litre of pure water
one gallon of pure water
one pint of pure water
The centre of gravity of a triangle is…
1/3 median from base
1/3 bisector from base
1/3 the height from base
A lifting machine moves with an effort, a distance of 200 cm, in order to raise it 0.5 m. The Velocity Ratio is...
0.25
4
40
Two Vectors are at 90 degrees to each other having magnitudes of 3N and 4N. The resultant is…
1N
7N
5N
Which of the following has no units?
Elasticity
Strain
Stress
