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 biology absorption by roots - the processes involved root pressure transportation in plants factors affecting the transport of water and minerals in plants

Root pressure can be measured by

  1. Attaching a barometer to the cut end of the stem

  2. Attaching a manometer to the cut end of the stem

  3. Attaching a thermometer to the cut end of the stem

  4. Attaching a potometer to the cut end of the stem.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The root pressure can be measured by attaching a suitable mercury manometer to the cut end of the stem. Root pressure provides a force which causes pushing of water in the stem. A continuous flow of water is maintained in the plants because the leaves transpire water through stomata and to replace the lost water the water drawn by the roots moves up.

Multiple choice biology absorption by roots - the processes involved root pressure transportation in plants factors affecting the transport of water and minerals in plants

Choose the correct answers from the alternatives given.
Root pressure can be measured by

  1. Osmometer

  2. Potometer

  3. Manometer

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

Different processes can be measured by various apparatus.

A. Osmometer is used to measure osmotic pressure (pressure needed to stop the solvent to pass through the semi-permeable membrane).
B. Potometer is used to measure transpiration rate (the rate at which transpiration occurs).
C. Manometer is used to measure the root pressure (pressure that is exerted by roots such that it allows sap to rise through the plant stem to the leaves).
D. Porometer is used to measure stomatal conductance in leaves.
Hence, the correct answer is 'Manometer'.

Multiple choice botany breath and blood of life stomata and transpiration transport in organisms long distance transport of water different types of circulatory systems

Which is used to measure the rate of transpiration?

  1. Atmometer

  2. Psychrometer

  3. Potometer

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

Atmometer is a device used to measure the rate of water evaporation from a wet surface to the atmosphere and can be used to measure the rate of evapotranspiration. 

A psychrometer is a device used to measure the rate of relative humidity in the atmosphere. 
Potometer is a device used to measure the rate of water uptake by plants  porometer is a device used to measure the area of the stomatal opening of leaves.
 So, the correct answer is 'Potometre'.

Multiple choice physics temperature and heat application of various thermometric scales different types of thermometers measuring temperature

A mercury thermometer, with a concave reflector behind the bulb, is placed in front of an electric fire. Which of the following combinations will cause the smallest reading on the thermometer?

  1. Black reflector, black bulb

  2. Black reflector, shiny bulb

  3. Shiny reflector, shiny bulb

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

A mercury thermometer, with a concave reflector behind the bulb, is placed in front of an electric fire.Black reflector, shiny bulb combinations will cause the smallest reading on the thermometer The black coating absorbs energy and warms up and warms the bulb by conduction.

Multiple choice physics heat - measurement application of various thermometric scales different types of thermometers measuring temperature introduction to temperature

A________is used to measure temperature

  1. Thermometer

  2. Barometer

  3. Manometer

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

A thermometer is a device that measures temperature or a temperature gradient. A thermometer has two important elements: (1) a temperature sensor (e.g. the bulb of a mercury-in-glass thermometer or the digital sensor in an infrared thermometer) in which some change occurs with a change in temperature, and (2) some means of converting this change into a numerical value (e.g. the visible scale that is marked on a mercury-in-glass thermometer or the digital readout on an infrared model). Thermometers are widely used in industry to monitor processes, in meteorology, in medicine, and in scientific research

Multiple choice physics heat - measurement application of various thermometric scales different types of thermometers measuring temperature introduction to temperature

Name the device for detecting and measuring small amount of thermal energy.

  1. Pyranometer

  2. Pyrometer

  3. Barrater

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

A bolometer is a device used for measuring the power of incident electromagnetic radiation via the heating of a material with a temperature-dependent electrical resistance.

Multiple choice physics electric current through conductors carbon resistance and colour codes for carbon resistance carbon resistors and their colour coding resistors

Resistors are generally colour coded to:

  1. Indicate the type of the circuit in which they are to be used

  2. Identify whether they are ohmic or non-ohmic

  3. Determine their values in ohm

  4. Determine whether they are wire wound or composition resistors
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Components and wires are coded with colors to identify their value and function. The colors brown, red, green, blue, and violet are used as tolerance codes on 5-band resistors only.

So,Resistors are generally colour coded to determine their values in ohm.
Therefore, C is correct option.

Multiple choice physics electric current through conductors carbon resistance and colour codes for carbon resistance carbon resistors and their colour coding resistors

A given resistor has the following colour scheme of the various strips on it : Brown, black, green and silver. Its value in ohm is :

  1. $1.0 \times 10^4 \pm 10\%$
  2. $1.0 \times 10^5 \pm 10\%$
  3. $1.0 \times 10^6 \pm 10\%$
  4. $1.0 \times 10^7 \pm 10\%$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Numbers attached for brown, black, green and silver are $1, 0, 5, \pm10\%$. Therefore the resistance of given resistor
$= 10 \times 10^5\  \Omega  \pm 10\%$.

Multiple choice physics electric current through conductors carbon resistance and colour codes for carbon resistance carbon resistors and their colour coding resistors

There are three red colored bands on a carbon resistor. What is its resistance ?

  1. $2.2$
  2. $2200$
  3. $\left( 2200\pm 20\% \right) $
  4. $1.76$ to $2.64$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

According to the color code of resistance,

code of red $=2$
code of red $=2$
code of red $=2$
The resistance of carbon resistor, $22\times 10^2 \pm20$%
$2200\pm20$%
The correct option is C.

Multiple choice physics electric current through conductors carbon resistance and colour codes for carbon resistance carbon resistors and their colour coding resistors

________  represents the most significant digits of the resistance value in finding the  resistance of carbon resistor.

  1. Last two color bands

  2. First two color bands

  3. Last color band only

  4. First color band only
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Since first and second color bands has higher multiplier, they represents the most significant digits of the resistance value in finding the  resistance of carbon resistor.

Therefore, B is correct option.