Physical World CBSE Questions & Answers

Physical World

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

Questions & Answers

1
The sun releases energy coming from
  • A
    electromagnetic waves
  • B
    weak electrical forces
  • C
    gravitational forces
  • D
    strong nuclear forces
    Correct
2
Weak Nuclear Force
  • A
    is responsible for holding the constituents of the nucleus together
  • B
    is responsible for holding the electrons and the nucleus together
  • C
    is responsible for a common form of radioactivity called beta decay
    Correct
  • D
    is responsible for holding the electrons of the nucleus together
3
The difference between nuclear forces and electromagnetic forces is that
  • A
    nuclear forces are mediated by photons compared to gluons for electromagnetic forces
  • B
    nuclear forces do not depend on charge
    Correct
  • C
    nuclear forces have longer range compared to electromagnetic forces
  • D
    nuclear forces are weaker compared to electromagnetic forces
4
In \(\beta \)-decay, the nucleus emits.
  • A
    an electron and a charged particle called neutrino
  • B
    a proton and a charged particle called anti neutrino
  • C
    a proton and a charged particle called neutrino
  • D
    an electron and an uncharged particle called neutrino
    Correct
5
The fundamental force with the shortest range is
  • A
    Electromagnetic Force
  • B
    Gravitational Force
  • C
    Weak Nuclear Force
    Correct
  • D
    Strong Nuclear Force
6
in every conservation principle
  • A
    a physical quantity for example total momentum does not change in a phenomenon .The quantity has the same value before and after the phenomenon.
    Correct
  • B
    a physical quantity like energy is converted into mass
  • C
    a physical quantity like mass is converted into energy
  • D
    a physical quantity changes to a form of energy
7
for motion under an external conservative force
  • A
    the mechanical energy i.e. the potential energy of a body is a constant
  • B
    the total mechanical energy i.e. the sum of kinetic and potential energy of a body is a constant
    Correct
  • C
    the total mechanical energy i.e. the sum of kinetic and potential energy of a body is a constant only if there is no motion
  • D
    the mechanical energy i.e. the kinetic energy of a body is a constant
8
The law of conservation of energy is.
  • A
    is valid only for applied mechanics
  • B
    is valid only for Newtonian mechanics
  • C
    thought to be valid across all domains of nature, from the microscopic to the macroscopic
    Correct
  • D
    is valid only for relativistic mechanics
9
Law of conservation of mass has been changed by Einstein to
  • A
    law of conservation of charge
  • B
    law of conservation of momentum
  • C
    law of conservation of mass and energy together i.e. mass + energy is conserved
    Correct
  • D
    law of conservation of angular momentum
10
Which of the following vectors are conserved for an isolated system?
  • A
    The angular momentum of a particle
  • B
    The force on a particle
  • C
    The linear momentum of a particle
  • D
    The total linear momentum
    Correct
11
Validity of the conservation of momentum is
  • A
    in all domains including domains where Newton’s laws may not be valid
    Correct
  • B
    in only those domains where quantum laws are valid
  • C
    in only cases involving billiard balls
  • D
    in only those domains where Newton’s laws are valid
12
All Conservation laws of nature are very useful in practice because
  • A
    It is applicable in all domains to solve problems using these laws
  • B
    it is often simpler to solve problems using these laws than using Newton’s laws
    Correct
  • C
    it is more acceptable to solve problems using these laws
  • D
    it is more modern to solve problems using these laws
13
Symmetry of nature with respect to translation (i.e. displacement) in time is
  • A
    None of these
  • B
    equivalent to the law of conservation of angular momentum
  • C
    equivalent to the law of conservation of energy
    Correct
  • D
    equivalent to the law of conservation of linear momentum
14
Michelson of Michelson-Morley experiment fame announced in 1905 that “physical discoveries in the future are a matter of the sixth decimal place.” According to him
  • A
    There cannot be any radically new theories in physics
    Correct
  • B
    It is necessary to improve the accuracy of the observations to the sixth place
  • C
    theories in physics will differ only in the sixth digit
  • D
    none of these
15
“Every great physical theory starts as a heresy and ends as a dogma”. Which of the following statements is a case of this aphorism?
  • A
    None of these
  • B
    Newton’s laws
    Correct
  • C
    Theory of gyroscopes
  • D
    Theory of rocket propulsion