Physics · General Awareness

Physics Measuring Instruments

1,180 Questions

Physics measuring instruments are essential tools used to measure various physical quantities. This topic covers devices like hygrometers, oscilloscopes, and sphygmomanometers. It is a highly scoring section in general science and general awareness examinations.

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Physics Measuring Instruments Questions

Multiple choice physics motion and measurement measuring length measurement of small and large distances measurement of distance

To minimise parallax error, the observer should place the object :

  1. as near to the scale of the ruler as possible and the eye must be directly above the scale

  2. as far to the scale of the ruler as possible and the eye must be directly above the scale

  3. as near to the scale of the ruler as possible and the eye must be to the right of the scale

  4. as near to the scale of the ruler as possible and the eye must be to the left of the scale
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

$Answer:-$ A

There are three simple ways of reducing parallax error in that case: 
1. Attach a straight object (like a ruler or straightened paperclip) to the thing you're measuring the displacement of, it should stick out of the object perpendicularly to the scale you're measuring the displacement on. 
2. Make sure that object is as close to your scale as possible, but not touching. 
3. Put your eyes level with the object, and as close to it as you safely can.

Multiple choice physics motion and measurement measuring length measurement of small and large distances measurement of distance

A student measure the height h of a convex mirror using spherometer. The legs of the spherometer are 4 cm apart and there are 10 divisions per cm on its linear scale and circular scale has 50 divisions. The student takes 2 as linear scale division and 40 as circular scale division. What is the radius of curvature of the convex mirror ?   

  1. $9.06 cm$
  2. $20.66 cm$
  3. $5.66 cm$
  4. $9.66 cm$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Least count of the spherometer is $LC=$ pitch/number of circular divisions $=\dfrac{1/10}{50}=0.002 cm$
The total reading for height is $h=MSR+(CSR\times LC)=(2\times 0.1)+(40\times 0.002)=0.28 cm$
The formula for radius of curvature is $R=\dfrac{l^2}{6h}+\dfrac{h}{2}=\dfrac{4^2}{6(0.28)}+\dfrac{0.28}{2}=9.66 cm$

Multiple choice physics units and measurement: error analysis accuracy of measurement accuracy and precision accuracy, precision and uncertainty in measurement

________ reflects quality of measuring instrument.

  1. Precision

  2. Accuracy

  3. Accuracy and Precision

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The degree to which several measurement provide answer very close to each other is known as precision. In other words, precision reflects the quality of measuring instrument.

Multiple choice chemistry chemical thermodynamics calorific value occurrence of carbon compounds in nature study of enthalpy

What is used to measure the calorific value of a substance?

  1. Barometer

  2. Bomb calorimeter

  3. Spectrometer

  4. Combustion chamber
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Barometer: To measure pressure.

Bomb calorimeter: To measure the heat output of combustion.

Spectrometer: To measure the absorption of light.

Combustion chamber: Chamber used for combustion.

Multiple choice zoology waste water story sewage treatment wastewater treatment - need and methods wastewater story

Which of the following equipment is used to study thermal behaviour of water? 

  1. MALDI-TOF

  2. Realtime PCR

  3. Differential scanning calorimeter

  4. SEM
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Differential scanning calorimetry or DSC is a thermoanalytical technique in which the difference in the amount of heat required to increase the temperature of a sample and reference is measured as a function of temperature.
  •  Hence, Differential scanning calorimeter is used to study the thermal behaviour of water.
  • So, the correct answer is 'Differential scanning calorimeter'.
Multiple choice zoology selection and evolution extinction extinctions environmental science

An instrument which measures concentration of C-14 directly is

  1. Accelerator mass spectrometer

  2. Spectroscope

  3. Geiger counter

  4. All the above.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Accelerator Mass Spectrometry (AMS) is the most precise method for directly measuring the concentration of C-14 isotopes in a sample.

Multiple choice biology physical resources air and winds wind energy air as a natural resource

The instrument which measures wind velocity is

  1. Lactometer

  2. Anemometer

  3. Hydrometer

  4. Barometer
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Anemometer is the instrument used to measure wind velocity. Hydrometer measures specific gravity (or relative density) of liquids. Barometer is used to measure atmospheric pressure. Lactometer measures cream content of milk.

Multiple choice biology physical resources air and winds wind energy air as a natural resource

The instrument which measures wind velocity is

  1. Lactometer

  2. Anemometer

  3. Hydrometer

  4. Barometer
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

An anemometer is the standard instrument used to measure wind speed or velocity. A barometer measures atmospheric pressure, a hydrometer measures liquid density, and a lactometer measures the purity of milk.

Multiple choice geography in search of the source of wind variations in atmospheric pressure properties of air pressure belts

Altimeter is a device to measure  ____________.

  1. Temperature

  2. Height

  3. Altitude

  4. Rainfall
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Altimeter is an instrument that measures the height of the land surface or any object such as an airplane. The most common types of altimeters are barometric. They determine altitude by measuring air pressure. As altitude increases, air pressure decreases. This is because the density of air is lower at high altitudes. Altimeters are important navigation instruments for aircraft and spacecraft pilots who monitor their height above the Earth’s surface. Skydivers and mountaineers also use altimeters to pinpoint their location in the sky or on the ground.

Multiple choice geography in search of the source of wind variations in atmospheric pressure properties of air pressure belts

Which one of the following is used for measuring the speed of wind ?

  1. Hygrometer

  2. Barometer

  3. Anemometer

  4. Thermometer
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Anemometer is a device which is used for measuring the speed of wind in the atmosphere. It also measures wind pressure. Anemometers are important tools for meteorologists, who study weather patterns. They are also important to the work of physicists, who study the way air moves. Anemometer has three or four cups attached to horizontal arms. The arms are attached to a vertical rod. As the wind blows, the cups rotate, making the rod spin. The stronger the wind blows, the faster the rod spins. The anemometer counts the number of rotations, or turns, which is used to calculate wind speed.

Multiple choice geography world of diversities elements of weather and climate :rainfall and air pressure diversified world environmental regions (zones)

Mercury or alcohol is used in the thermometers.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mercury or alcohol is used in the thermometers. A thermometer is a device that is used to measure the temperature. Alcohol thermometer and mercury thermometer are two types of thermometers that are composed of a bulb and a marked glass tube. The main difference between alcohol and mercury thermometer is that the bulb of mercury thermometer is filled with mercury whereas the bulb of alcohol thermometer is filled with alcohol. The alcohol thermometers are less toxic, whereas the mercury thermometers are highly toxic. 

Multiple choice physics free, damped and forced oscillations resonance: examples and uses resonance oscillatory motion

Which one does not work on principles of resonance?

  1. T.V

  2. Radio

  3. Microwave oven

  4. Bulb
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Resonance in an electrical circuit is a phenomenon in which the inductive reactance and the capacitive reactance become equal and cancel each other.

As a result, the impedance of the circuit becomes the least and maximum current flows through the circuit. This happens only at a particular frequency of the AC power supply, known as resonant frequency. 
All the devices except bulb work on this principle. The circuit in them is tuned in order to make their resonant frequency matching with the desired one. This is done by adjusting the values of the inductor or the capacitor.
In a bulb, there is only pure resistance and no reactive component. There is no question of resonance.