Units and Measurements Test

Result

Units and Measurements Test - 28

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

Which of the following is a dimensional constant?

A
Refractive index

B
Dielectric constant

C
Relative density

D
Gravitational constant

Solution

Gravitational constant also known as universal gravitational constant has a symbol $$G$$ and has a dimension $$\left[ { M }^{ -1 }{ L }^{ 3 }{ T }^{ -2 } \right] $$ while others are dimensionless constant.
Question 2
1 / -0

The dimension of length for coefficient of viscosity is

A
-1

B
+1

C
-2

D
+2

Solution

Units of coefficient of viscosity is $$kgm^{-1}s^{-1}$$ i.e. $$ML^{-1}T^{-1}$$
Therefore the dimension of length(L) is $$-1$$.
Question 3
1 / -0

Place the odd unit out.

A
kilowatt hour

B
joule second

C
watt second

D
electron volt

Solution

$$\left[ kilowatt \ hour \right] =\left[ watt \ second \right] =\left[ electron \ volt \right] =\left[ { M }^{ 1 }{ L }^{ 2 }{ T }^{ -2 } \right] $$
And they have the unit of energy while joule second is the odd one.
Question 4
1 / -0

$$\sqrt {\mu_0\epsilon_0}$$ has the dimensions

A
$$[M^0LT^{-1}]$$

B
$$[M^0L^{-1}T]$$

C
$$[M^2L^3T^{-1}]$$

D
$$[M^{-1}L^3T^{-2}]$$

Solution

Both $$\mu _o$$ and $$\epsilon _o$$ are related by
$$\displaystyle c=\frac {1}{\sqrt {\mu _o\epsilon _o}}$$; c-speed of light.

So, the units of $$\sqrt {\mu _o\epsilon _o}$$ is inverse of speed, i.e. $$M^oL^{-1}T^1$$
Question 5
1 / -0

Which is most accurate?

A
3 m

B
3.0 m

C
3.00 m

D
3.000 m

Solution

The one with more significant figures in the decimal is more accurate.
Option D.
Question 6
1 / -0

How many significant figures are there in 30100?

A
1

B
3

C
5

D
none of these

Solution

As we know zeroes only after a non zero digit and after decimal and zeroes between any two non zero digits are significant.
Therefore, option (B) is correct.
Question 7
1 / -0

Which of the following have the same dimensions?

A
impulse and momentum

B
specific heat and latent heat

C
moment of inertia and force

D
thrust and surface tension

Solution

Impulse is defined as the change in momentum.
Impulse $$I = \Delta p = mv - mu$$
Hence, both Impulse and momentum have the same units/dimensions.
Question 8
1 / -0

Dimensions of $$\dfrac {1}{\mu_o\epsilon_o}$$, where symbols have their usual meaning, are

A
$$[L^{-1}T]$$

B
$$[L^{-2}T^{2}]$$

C
$$[L^{2}T^{-2}]$$

D
$$[LT^{-1}]$$

Solution

We have:
$$\displaystyle c=\frac {1}{\sqrt {\mu _o\epsilon _o}}$$
$$\displaystyle c^2=\frac {1}{\mu _o\epsilon _o}$$
$$c=m/s=LT^{-1}$$
$$\Rightarrow c^2=L^2T^{-2}$$
Question 9
1 / -0

The dimensions of electromotive force in terms of current A are

A
$$[MT^{-2}A^{-2}]$$

B
$$[ML^{2}T^{-2}A^2]$$

C
$$[ML^{2}T^{-2}A^{-2}]$$

D
$$[ML^{2}T^{-3}A^{-1}]$$

Solution

Electromotive force, also called emf (measured in volts), is the voltage developed by any source of electrical energy such as a battery or dynamo.
Electromotive force $$=$$ potential difference $$ =V=\dfrac {W}{q}=\dfrac {ML^2T^{-2}}{AT}=[ML^2T^{-3}A^{-1}]$$
Question 10
1 / -0

The dimensions of pressure gradient are

A
$$[ML^{-2}T^{-2}]$$

B
$$[ML^{-2}T^{-1}]$$

C
$$[ML^{-1}T^{-1}]$$

D
$$[ML^{-1}T^{-2}]$$

Solution

Pressure gradient is given as, $$P=\dfrac {\text {Change in Pressure}}{changedistance}$$
$$\left[ P \right] =\dfrac {ML^{-1}T^{-2}}{L}$$$$=[ML^{-2}T^{-2}]$$

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Units and Measurements Test - 28

Result

Units and Measurements Test - 28

Score

-

Rank

-

SHARING IS CARING

Question 1

Refractive index

Dielectric constant

Relative density

Gravitational constant

Solution

Question 2

-1

+1

-2

+2

Solution

Question 3

kilowatt hour

joule second

watt second

electron volt

Solution

Question 4

$$[M^0LT^{-1}]$$

$$[M^0L^{-1}T]$$

$$[M^2L^3T^{-1}]$$

$$[M^{-1}L^3T^{-2}]$$

Solution

Question 5

3 m

3.0 m

3.00 m

3.000 m

Solution

Question 6

1

3

5

none of these

Solution

Question 7

impulse and momentum

specific heat and latent heat

moment of inertia and force

thrust and surface tension

Solution

Question 8

$$[L^{-1}T]$$

$$[L^{-2}T^{2}]$$

$$[L^{2}T^{-2}]$$

$$[LT^{-1}]$$

Solution

Question 9

$$[MT^{-2}A^{-2}]$$

$$[ML^{2}T^{-2}A^2]$$

$$[ML^{2}T^{-2}A^{-2}]$$

$$[ML^{2}T^{-3}A^{-1}]$$

Solution

Question 10

$$[ML^{-2}T^{-2}]$$

$$[ML^{-2}T^{-1}]$$

$$[ML^{-1}T^{-1}]$$

$$[ML^{-1}T^{-2}]$$

Solution

User

Question Analysis

My Perfomance

Score

-

Rank

-

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.