Physics miscellaneous

Physics miscellaneous

Easy Questions

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Physics miscellaneous
  1. The minimum number of forces to keep a particle in equilibrium is








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    When the resultant of all forces acting on a particle is zero, the particle is in equilibrium. The equilibrium of a particle to which a single force is applied may be maintained by the application of a second force that is equal in magnitude and direction, but opposite in sense, to the first force. This second force, which restores equilibrium, is called the equilibrant. Hence, the minimum number of forces to keep a particle in equilibrium is two.

    Correct Option: B

    When the resultant of all forces acting on a particle is zero, the particle is in equilibrium. The equilibrium of a particle to which a single force is applied may be maintained by the application of a second force that is equal in magnitude and direction, but opposite in sense, to the first force. This second force, which restores equilibrium, is called the equilibrant. Hence, the minimum number of forces to keep a particle in equilibrium is two.

  1. The work done by the string of a simple pendulum during one complete oscillation is equal to








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    Work done by the string of the simple pendulum during one complete oscillation is zero. Tension in the string exactly cancels the component parallel to the string. This leaves a net restoring force back toward the equilibrium position as equal to zero.

    Correct Option: D

    Work done by the string of the simple pendulum during one complete oscillation is zero. Tension in the string exactly cancels the component parallel to the string. This leaves a net restoring force back toward the equilibrium position as equal to zero.

  1. Stationary wave is formed by








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    Stationary or standing waves are formed in a medium when two waves having equal amplitude and frequency moving in opposite directions along the same line, interfere in a confined space. Generally, such waves are formed by the superposition of a forward wave and the reflected wave. Both longitudinal and transverse types of waves can form a stationary wave.

    Correct Option: D

    Stationary or standing waves are formed in a medium when two waves having equal amplitude and frequency moving in opposite directions along the same line, interfere in a confined space. Generally, such waves are formed by the superposition of a forward wave and the reflected wave. Both longitudinal and transverse types of waves can form a stationary wave.

  1. Two bodies kept at a certain distance feel a gravitational force F to each other. If the distance between them is made double the former distance, the force will be








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    Gravitational force

    F = G ×
    m1m2
    d2

    where F is the gravitational force, m1 and m2 are the masses of two objects, G is the universal gravitational constant and d is the distance between the two objects. Since the gravitational force is inversely proportional to the square of the distance, if the distance between the two bodies is doubled, the force of gravity is reduced to one-fourth its original value.

    Correct Option: D

    Gravitational force

    F = G ×
    m1m2
    d2

    where F is the gravitational force, m1 and m2 are the masses of two objects, G is the universal gravitational constant and d is the distance between the two objects. Since the gravitational force is inversely proportional to the square of the distance, if the distance between the two bodies is doubled, the force of gravity is reduced to one-fourth its original value.

  1. If both the mass and the velocity of a body is increased to twice of their magnitude, the kinetic energy will increase by








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    If m be the mass and v be the velocity, then Kinetic Energy is given by KE

    =
    1
    		(mv2) =
    1
    		(2m × 4v2)
    22

    =
    8
    		mv2 = 4mv2
    2

    So, if both mass and velocity are doubled, the kinetic energy increases by 4 times.

    Correct Option: B

    If m be the mass and v be the velocity, then Kinetic Energy is given by KE

    =
    1
    		(mv2) =
    1
    		(2m × 4v2)
    22

    =
    8
    		mv2 = 4mv2
    2

    So, if both mass and velocity are doubled, the kinetic energy increases by 4 times.