Physics Classes

Tag: science

  • Alternating current objective questions with answers

    In this blog physics classes by Nayan jha providing objective questions and answers , which contain multiple choice , assertion reason and case study based questions with explanation( complete solution.

    To download the pdf all questions and its answer click here-

    For question numbers 86-100, two statements are given-one labelled Assertion (A) and the other labelled Reason (R).
    Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
    (a) Both A and R are true and R is the correct explanation of A
    (b) Both A and R are true but R is NOT the correct explanation of A
    (c) A is true but R is false
    (d) A is false and R is also false

    1. Assertion (A) : Long distance transmission
      of A.C. is carried out at extremely high voltage.
      Reason (R): For large distance, voltage has
      to be large….
    2. Assertion (A) : An electric lamp connected
      in series with a variable capacitor and A.C.
      source, its brightness increases with increase
      in capacitance.
      Reason (R): Capacitive reactance decreases
      with increase in capacitance of capacitor.
    3. Assertion (A) : A transformer cannot work
      on D.C. supply.
      Reason (R): D.C. changes neither in magnitude
      nor in direction.
    4. Assertion (A) : Step-down transformer
      increases the current.
      Reason (R): Transformer obeys the law of
      conservation of energy.

    To download complete assignment of these questions and answer (PDF)click here-

  • How forces affects motion

    class 9 Chapter-6 (physics)

    In Chapter 4, you learnt to describe the motion of an object in terms
    of its position, velocity and acceleration. But you did not consider
    what causes motion. Is there an underlying cause for a change in
    position and velocity of an object? What is the nature of this cause?
    Do all motions require a cause? In this chapter, we will investigate
    what causes changes in the motion of objects. We will also discuss
    Newton’s three laws of motion and learn how to apply them.
    6.1 The Concept of Force
    Grade 8
    Curiosity
    Chapter 5
    You may recall learning earlier that a force can make an
    object move from rest, change the speed and direction
    of motion of a moving object, and can even change the
    shape of an object. For example, a ball at rest starts moving when
    you apply a force, a force applied by a cricket bat on a cricket ball
    changes its direction, and a lemon can be squeezed by the force
    applied by your fingers.

    To download the entire chapter click here-