Physics
##### ASSERTION

In the measurement of physical quantities direct and indirect methods are used.

##### REASON

The accuracy and precision of measuring instruments along with errors in measurements should be taken into account, while expressing the result.

##### ANSWER

Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

##### SOLUTION
Direct measurement refers to directly measuring the quantity for which the experiment is performed while indirect measurement means first measuring some primary quantities and then using them to calculate the required quantity. It has no relation to accuracy and precision.
Accuracy must be taken into account to know the closeness of result to actual value while precision is required to get the correlation between different values which are observed in repeatedly performing an experiment.
Hence both statements are correct but second one does not explain first.

You're just one step away

Create your Digital Resume For FREE on your name's sub domain "yourname.wcard.io". Register Here!

Assertion & Reason Medium Published on 18th 08, 2020
Questions 244531
Subjects 8
Chapters 125
Enrolled Students 218

#### Realted Questions

Q1 Single Correct Medium
If $E, M, J$ and $G$ denote energy, mass, angular momentum and gravitational constant respectively, then $\dfrac{EJ^2}{M^5G^2}$ has the dimensions of
• A. Length
• B. Mass
• C. Time
• D. Angle

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q2 Single Correct Medium
A cube has a side of length 1.2 x $10^{-2}$. Its volume upto correct significant figures is
• A. 1.7 x $10^{-6}m^3$
• B. 1.73 x $10^{-6}m^3$
• C. 1.78 x $10^{-6}m^3$
• D. 1.732 x $10^{-6}m^3$

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q3 Single Correct Medium
Which has least count of 0.001 cm. The number of division through which zero mass has crossed the refrence line is 2. The zero error is-
• A. 0.005
• B. -0.005 cm
• C. +0.02
• D. + 0.02 cm

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q4 Single Correct Medium
If the centrifugal force on a body moving on the circumference of a circle is related to the mass $M$, velocity $V$ and radius of the circular orbit r as $F\alpha { M }^{ a }{ V }^{ b }{ R }^{ c }$, then the values of $a, b$ and $c$ respectively are :
• A. 1, 1, 2
• B. 1, 2, 1
• C. 1, 2, 2
• D. 1, 2, -1

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q5 Single Correct Medium
The equation of a wave is given by $\displaystyle Y = A\,sin\,\omega \left ( \frac {x} {v} - k \right )$ where $\omega$ is the angular velocity and $v$ is the linear velocity. The dimensions of $k$ is ?
• A. $[\displaystyle LT]$
• B. $[\displaystyle T]$
• C. $[ T^{-1}]$
• D. $[ T^{2}]$

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020