Physics · General Awareness

Physics Measuring Instruments

1,123 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.

Pressure and humidity instrumentsElectrical measuring devicesMedical physics toolsNavigational instruments

Physics Measuring Instruments Questions

Multiple choice physics forces in fluids hydrometer and lactometer comparing density - relative density principle of floatation and its applications

Hydrometer is based on the principle of ___

  1. Principle of buoyancy

  2. Principle of floatation

  3. Pascals law

  4. Charle's law
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Hydrometer is based on the principle of floatation i.e., the weight of the liquid object displaced by the immersed portion of the hydrometer is equal to the weight of the hydrometer. 

Multiple choice physics forces in fluids hydrometer and lactometer comparing density - relative density principle of floatation and its applications

Match the following

1.Bulb filled with lead shots or mercury a. Increases sensitivity
2.The bulb helps the hydrometer to float b. Reduces center of gravity
3. Mercury c. Increases upthrust on the hydrometer
4. Narrow stem d. Gravity bulb

  1. 1-b, 2-d, 3-c, 4-a

  2. 1-b, 2-c, 3-a, 4-d

  3. 1-a, 2-d, 3-b, 4-c

  4. 1-d, 2-c, 3-b, 4-a
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Common hydrometer consists of three main parts the stem, the large bulb (floating bulb) and the small bulb filled with mercury or lead shots (gravity bulb). The floating bulb increases the upthrust on the hydrometer because when it submerges in the water completely it increases the weight of the water displaced. The smaller bulb is filled with lead shots or mercury which helps in lowering the center of gravity which enables the hydrometer to float vertically in the liquid. Thus the smaller bulb is called the gravity bulb. The narrow stem helps the hydrometer to sink effectively when dropped in a liquid with higher or lower relative density thus increasing the sensitivity of the hydrometer.

Multiple choice physics forces in fluids hydrometer and lactometer comparing density - relative density principle of floatation and its applications

Hydrometer is used to determine which of the following?

  1. Specific gravity of liquids.

  2. Boiling point of water.

  3. Specific heat of a matter.

  4. Specific humidity
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Hydrometer is a devide used to determine the specific density of liquids.

A hydrometer is usually made of glass, and consists of a cylindrical stem and a bulb weighted with mercury to make it float upright. The liquid to test is poured into a tall container and the hydrometer is gently lowered into the liquid until it floats freely. The point at which the surface of the liquid touches the stem of the hydrometer correlates to specific gravity. Hydrometers usually contain a scale inside the stem, so that the person using it can read specific gravity. 

Multiple choice physics forces in fluids hydrometer and lactometer comparing density - relative density principle of floatation and its applications

Hydrometers usually contain a scale inside the stem, so that the person using it can read specific gravity.Is the statement True or False

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A hydrometer is usually made of glass, and consists of a cylindrical stem and a bulb weighted with mercury to make it float upright. The liquid to test is poured into a tall container and the hydrometer is gently lowered into the liquid until it floats freely. The point at which the surface of the liquid touches the stem of the hydrometer correlates to specific gravity. Hydrometers usually contain a scale inside the stem, so that the person using it can read specific gravity. 
Multiple choice physics forces in fluids hydrometer and lactometer comparing density - relative density principle of floatation and its applications

Hydrometers are used to serve what purpose?

  1. For determining density of liquid

  2. Pressure measurement

  3. Viscosity measurement

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

Answer is A

A hydrometer is an instrument used to measure the specific gravity (relative density) of liquids; that is, the ratio of the density of the liquid to the density of water. A hydrometer is usually made of glass and consists of a cylindrical stem and a bulb weighted with mercury or lead shot to make it float upright

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'.