Tag: measurement of distance

Questions Related to measurement of distance

It has long been an objective in metrology to define the kilogram in terms of a fundamental constant, in the same way that the ____________________ is now defined in terms of the speed of light. 

physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

  1. centimetre

  2. metre

  3. decimetre

  4. none of the above

Show answer
Correct Option: B
Explanation:

Metre is the SI unit used for measuring the distance which is defined taking speed of light as a reference.

100 kg of Silver has volume $10{ m }^{ 3 }.$ The density of silver in C.G.S is

physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

  1. $10{ g/cm }^{ 3 }$

  2. $0.05{ g/cm }^{ 3 }$

  3. $0.01{ g/cm }^{ 3 }$

  4. None of these

Show answer
Correct Option: C
Explanation:
Given

The mass of silver $= 100 kg$

Volume of the cube $= 10 m^3$

We know that the density of a substance is given by the following formula

$Density = \dfrac{Mass}{Volume}$

Density of the silver $= \dfrac{100}{10} kg/m^3=10kg/m^3$

Now we know that $1 kg = 1000 gm = 10^3 gm$

and $1 m = 100 cm$

$⇒ 1 m^3 = 100^3 \,cm^3 = 10^6 cm^3$

Therefore, the density of silver in cgs $= \dfrac{10\times 10^3}{10^6} gm/cm^3=0.01\,gm/cm^3$

Which of the following defines 1 kg of mass correctly?

physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

  1. When a force of 1N produced an acceleration of $\displaystyle 1{ m }/{ { s }^{ 2 } }$ in a body, then the mass is said to be 1 kg

  2. When a force of 10N produced an acceleration of $\displaystyle 10{ m }/{ { s }^{ 2 } }$ in a body, then the mass of body is said to be 1 kg

  3. When a force of 100N produced an acceleration of $\displaystyle 1{ m }/{ { s }^{ 2 } }$ in a body, then the mass of body is said to be 1 kg

  4. All

Show answer
Correct Option: A
Explanation:

When a force of 1 N produced an acceleration of $\displaystyle 1{ m }/{ { s }^{ 2 } }$ in a body, then the mass of body is said to be 1 kg.(definition)

The kilogram, originally defined as the mass of ___________________at the temperature of maximum density, was known as the Kilogram of the Archives.

physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

  1. one cubic decimeter of gasoline

  2. one cubic decimeter of water

  3. one cubic decameter of water

  4. one square decameter of water

Show answer
Correct Option: B
Explanation:

The kilogram, defined as the mass of one cubic decimeter of water at $4^o C$ is known as kilogram of the Archives.

The kilogram is the SI base unit of mass and is equal to the mass of the international prototype of the kilogram , a ___________standard that is kept at the International Bureau of Weights and Measures (BIPM) .

physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

  1. platinum-iridium

  2. platinum

  3. iridium

  4. all of the above

Show answer
Correct Option: A
Explanation:

Platinum-iridium is the standard that is kept at the International Bureau of Weights and Measures (BPIM).

______________________ is/are linked through its/their definitions to the mass of the platinum-iridium cylinder stored in a vault near Paris.

physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

  1. ampere

  2. mole

  3. candela

  4. all of the above

Show answer
Correct Option: D
Explanation:

Ampere, Mole and Candela are linked through their definitions to the mass of the platinum-iridium cylinder stored in a vault near Paris.

$10^{-3}$ gram is called the

physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

  1. kilogram

  2. milligram

  3. decigram

  4. microgram

Show answer
Correct Option: B
Explanation:

1 milligram (mg) = $10^{-3}$ gram (g)