Units And Measurements CBSE Questions & Answers

Units And Measurements

This is Physics Class 11 Units and Measurements CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
When two quantities are added or subtracted, the absolute error in the final result is
  • A
    absolute value of the sum of individual quantities
  • B
    absolute value of the sum of errors of individual quantities
  • C
    absolute value of the difference of errors of individual quantities
  • D
    the sum of the absolute errors in the individual quantities
    Correct
2
When two quantities are multiplied or divided, the relative error in the result is
  • A
    the difference of the absolute errors in the multipliers
  • B
    the difference of the relative errors in the multipliers
  • C
    the sum of the relative errors in the multipliers
    Correct
  • D
    the sum of the absolute errors in the multipliers
3
The relative error in a physical quantity raised to the power k is.
  • A
    k times the relative error in the individual quantity
    Correct
  • B
    (k – 1) times the absolute error in the individual quantity
  • C
    (k – 1) times the relative error in the individual quantity
  • D
    k times the absolute error in the individual quantity
4
The significant figures of a number
  • A
    are those digits that carry meaning contributing to its accuracy
    Correct
  • B
    are all non zero digits
  • C
    are those that are at odd positions after decimal
  • D
    are those that are at even positions after decimal
5
The dimensions of a physical quantity are
  • A
    the sum of all the number of base quantities
  • B
    the sum of the exponents of base quantities
  • C
    the mean of the exponents of base quantities
  • D
    the powers (or exponents) to which the base quantities are raised to represent that quantity
    Correct
6
According to the principle of homogeneity of dimensions
  • A
    we can add similar physical quantities
  • B
    we can subtract similar physical quantities
  • C
    we can add or subtract similar physical quantities
    Correct
  • D
    we can add or subtract any physical quantities
7
If an equation is dimensionally consistent
  • A
    dimensions of the left hand side and right hand side of the equation are the same
    Correct
  • B
    dimensions of the left hand side and right hand side of the equation differ by 2
  • C
    dimensions of the left hand side and right hand side of the equation are different
  • D
    dimensions of the left hand side and right hand side of the equation differ by 1
8
Dimensional analysis can be used to
  • A
    check the validity of an equation
  • B
    check the order of an equation
  • C
    None of these
  • D
    check the dimensional consistency of equations
    Correct
9
A dimensionally consistent equation
  • A
    is nearly correct
  • B
    is not necessarily correct
    Correct
  • C
    is always correct
  • D
    is necessarily correct
10
Electric charge is expressed in SI units as
  • A
    derived unit
    Correct
  • B
    fundamental unit
  • C
    complex unit
  • D
    a base unit
11
The units of pressure are the same as the units of
  • A
    plasticity
  • B
    stress
    Correct
  • C
    elasticity
  • D
    strain
12
The volume of a cube of side 2 cm is equal in \({{\rm{m}}^{\rm{3}}}\) to
  • A
    0.08
  • B
    0.008
  • C
    0.0008
  • D
    \(8.0 \times {10^{ - 6}}\)
    Correct
13
The surface area of a solid cylinder of radius 2.0 cm and height 10.0 cm in \({\rm{m}}{{\rm{m}}^{\rm{2}}}\) is equal to
  • A
    15
  • B
    1500
  • C
    \(1.5 \times {10^4}\)
    Correct
  • D
    150
14
How many meters does a vehicle moving with a speed of 18 km \({{\rm{h}}^{ - {\rm{1}}}}\) covers 1 s
  • A
    5.0
    Correct
  • B
    4.5
  • C
    6
  • D
    4
15
The relative density of lead is 11.3. Its density in g \({\rm{c}}{{\rm{m}}^{ - {\rm{3}}}}\) is
  • A
    1130
  • B
    1.13
  • C
    11.3
    Correct
  • D
    113