1. (A) is correct. In a cyclotron, a charged particle undergoes continuous acceleration. It speeds up between the dees due to an alternating electric field but moves in circular motion inside the dees at constant speed due to the magnetic field. The repeated acceleration increases its energy, making itRead more

    (A) is correct. In a cyclotron, a charged particle undergoes continuous acceleration. It speeds up between the dees due to an alternating electric field but moves in circular motion inside the dees at constant speed due to the magnetic field. The repeated acceleration increases its energy, making it spiral outward.

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  2. (A) is correct. The time period T of a charged particle in a uniform magnetic field is given by T = 2πm/qB . It depends on the mass m, charge q and magnetic field B, but not on the speed of the particle. Thus, the time period remains constant regardless of speed changes. For more visit here: https:/Read more

    (A) is correct. The time period T of a charged particle in a uniform magnetic field is given by
    T = 2πm/qB . It depends on the mass m, charge q and magnetic field B, but not on the speed of the particle. Thus, the time period remains constant regardless of speed changes.

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  3. (A) is correct. The force per unit length between two parallel current-carrying wires is given by F ∝ I₁ I₂/d, where d is the distance between them. If the distance is doubled, the force becomes 1/2 of the original value. Thus, the force between the wires is halved. For more visit here: https://www.Read more

    (A) is correct. The force per unit length between two parallel current-carrying wires is given by
    F ∝ I₁ I₂/d, where d is the distance between them. If the distance is doubled, the force becomes
    1/2 of the original value. Thus, the force between the wires is halved.

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  4. The correct answer is (B) B. The magnetic field inside a long solenoid is given by: B = μonI Where n = number of turns per unit length and I = current. If the number of turns is halved (n/2) and current is doubled (2I), the new magnetic field becomes: B' = μ0 ​ n/2 2I = μ0 ​nI = B Answer: (B) B. httRead more

    The correct answer is (B) B.

    The magnetic field inside a long solenoid is given by:
    B = μonI
    Where n = number of turns per unit length and
    I = current.
    If the number of turns is halved (n/2) and current is doubled (2I), the new magnetic field becomes:
    B’ = μ0

    n/2 2I = μ0
    ​nI = B
    Answer: (B) B.

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  5. The current sensitivity of a moving coil galvanometer is given by: Si = N AB/K Where: N = Number of turns A = Area of coil B = Magnetic field K= Torsional constant When the resistance (R) of the galvanometer increases by a factor of 3, the voltage sensitivity (Sv) is given by: Sv = Si/R Since currenRead more

    The current sensitivity of a moving coil galvanometer is given by:
    Si = N AB/K
    Where:
    N = Number of turns
    A = Area of coil
    B = Magnetic field
    K= Torsional constant
    When the resistance (R) of the galvanometer increases by a factor of 3, the voltage sensitivity (Sv) is given by:
    Sv = Si/R
    Since current sensitivity increases by 35%, we have:

    Sv′ = 1.35 × Si/3R = 1.35/3 × Sv = 0.45 ​× Sv
    Hence, the voltage sensitivity decreases by 55% (100%−45%
    Answer: (C) 55%

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