WorksheetsJohnson Controls India Assessment Test 04
Total questions: 50
Worksheet time: 50mins
The sum of first 20 natural numbers is:
190
200
210
220
A man walks 6 km/hr instead of 4 km/hr and saves 30 minutes. The distance is:
12 km
10 km
8 km
6 km
The average of 40 numbers is 35. If two numbers 45 and 55 are removed, the new average is:
34
34.5
35
36
If 5 men can paint a wall in 20 days, then 10 men can paint it in:
5 days
10 days
15 days
20 days
The compound interest on ₹10,000 at 5% per annum for 2 years is:
₹1000
₹1025
₹1050
₹1100
A bag contains 4 red, 5 blue, and 6 green balls. Probability of drawing a blue ball is:
5/15
5/14
5/13
5/12
The next number in the series: 3, 9, 27, 81, ?
162
243
324
369
If a train passes a platform of 250 m in 25 sec at 54 km/h, the train length is:
100 m
150 m
200 m
250 m
The ratio of ages of A and B is 3:4. After 6 years, ratio becomes 4:5. Present ages are:
12, 16
18, 24
24, 32
30, 40
A shopkeeper allows 20% discount on a product of marked price ₹500. Selling price is:
₹380
₹400
₹420
₹440
The unit of magnetic flux is:
Weber
Tesla
Henry
Coulomb
In AC circuits, reactive power is measured in:
Watt
VAR
VA
kWh
A three-phase supply frequency in India is:
50 Hz
60 Hz
25 Hz
100 Hz
The material used for transformer core is:
Copper
Aluminum
Silicon steel
Brass
In rectifiers, ripple factor is:
Average value / RMS value
RMS value / Average value
AC component / DC component
None
A zener diode is used for:
Rectification
Voltage regulation
Amplification
Oscillation
The maximum power transfer theorem states that:
Load resistance = Source resistance
Load resistance > Source resistance
Load resistance < Source resistance
None
Which motor is commonly used in household fans?
DC motor
Universal motor
Induction motor
Stepper motor
In electronics, IC stands for:
Internal Circuit
Integrated Circuit
Instantaneous Current
Independent Circuit
Which effect is used in transformers?
Photoelectric effect
Electromagnetic induction
Hall effect
Thermoelectric effect
Which thermocouple has the highest temperature range?
J-type
K-type
R-type
T-type
The sensitivity of an instrument is defined as:
Output per unit input
Error / Input
Range / Input
Hysteresis
Which device converts pressure into displacement?
Thermistor
Bourdon tube
Thermocouple
Hygrometer
The device used for speed measurement is:
Tachometer
Strain gauge
Load cell
Thermopile
Hysteresis error occurs due to:
Magnetic property
Mechanical friction
Elastic property of material
All of the above
The working principle of piezoelectric sensors is:
Pressure produces voltage
Voltage produces pressure
Temperature changes resistance
Inductance changes with displacement
A rotameter is used to measure:
Pressure
Temperature
Flow rate
Level
The accuracy of a measuring instrument is expressed as:
Percentage of true value
Percentage of range
Absolute error
Relative error
The function of a transducer is to:
Convert electrical to mechanical
Convert one form of energy to another
Store energy
Amplify signal
LVDT works on the principle of:
Induction
Resistance
Capacitance
Piezoelectric
Heat transfer rate in conduction is proportional to:
Temperature difference
Square of temperature
Cube of temperature
None
In HVAC, COP of a chiller is defined as:
Work done / Heat absorbed
Heat absorbed / Work done
Heat rejected / Work input
Heat rejected / Heat absorbed
The refrigerant R-717 is:
Ammonia
R-12
R-22
R-134a
The main function of an evaporator in refrigeration is:
Absorb heat from surroundings
Reject heat
Compress refrigerant
Regulate pressure
Which heat exchanger has the highest efficiency?
Counterflow
Parallel flow
Cross flow
Shell-and-tube
The most efficient cycle for gas turbine is:
Carnot cycle
Brayton cycle
Rankine cycle
Otto cycle
The volumetric efficiency of compressors decreases due to:
Clearance volume
High speed
Cooling
Lubrication
In HVAC, AHU stands for:
Air Handling Unit
Air Heating Utility
Ambient Humidity Unit
Automatic Heating Unit
Which law governs radiation heat transfer?
Stefan–Boltzmann law
Fourier’s law
Newton’s law of cooling
Darcy’s law
The maximum COP is achieved when:
Temperature difference is maximum
Temperature difference is minimum
Pressure ratio is maximum
Refrigerant flow is high
The function of condenser in refrigeration is:
Reject heat
Absorb heat
Increase pressure
Increase velocity
Shell-and-tube heat exchangers are widely used because:
Compact design
Easy maintenance
High efficiency
All of the above
In mechanical ventilation, CFM stands for:
Cubic Feet per Minute
Cooling Fan Motor
Centrifugal Flow Meter
Critical Flow Measurement
The refrigerant property with environmental significance is:
GWP & ODP
Density
Specific heat
Conductivity
Which compressor is commonly used in high-capacity chillers?
Reciprocating
Screw
Centrifugal
Scroll
A heat exchanger fouling leads to:
Increase in heat transfer
Decrease in heat transfer
No effect
Improved efficiency
In psychrometry, WBT stands for:
Wet Bulb Temperature
Warm Base Test
Water Balance Trend
Weighted Base Temperature
The refrigeration cycle used in aircrafts is:
Vapor compression
Vapor absorption
Air refrigeration
Lithium bromide cycle
Which international body provides HVAC standards?
ASHRAE
IEEE
ASTM
BIS
The main purpose of an economizer in HVAC systems is:
Sub-cooling refrigerant to save energy
Increase compressor size
Increase condenser pressure
Store refrigerant
