Two particles A and B having equal charges, after being accelerated through the same potential difference enter into a region of uniform magnetic field and the particles describe circular paths of radii R₁ and R₂, […]
If the magnetising field on a ferromagnetic material is increased, its permeability
Options
(a) decrease (b) increase (c) is unaffected (d) may be increase or decrease
Correct Answer:
decrease
Explanation:
Magnetic permeability of substance, […]
The dimensions of magnetic field intensity B are
Options
(a) MLT⁻²A⁻¹ (b) MT⁻²A⁻¹ (c) ML²TA⁻² (d) M²LT⁻²A⁻¹
Correct Answer:
MT⁻²A⁻¹
Explanation:
Dimensions of B = [MT⁻²A⁻¹] F = Bil sin θ [MLT⁻²] = [B] […]
Core of electromagnets are made of ferromagnetic material which has
Options
(a) low permeability and high retentivity (b) high permeability and low retentivity (c) low permeability and low retentivity (d) high premeability and […]
Equal currents are passing through two very long and straight parallel wires in the same direction. They will
Options
(a) attract each other (b) repel each other (c) lean towards each other (d) […]
Identify the paramagnetic substance
Options
(a) Iron (b) Aluminium (c) Nickel (d) Hydrogen
Correct Answer:
Aluminium
Explanation:
No explanation available. Be the first to write the explanation for this question by commenting […]
A tangent galvanometer has a coil of 50 turns and a radius of 20 cm. The horizontal component of earth’s magnetic field is Bʜ=3×10⁻⁵ T. What will be the current which gives a deflection of […]
At place on earth, the vertical component of earth’s magnetic field is √3 times its horizontal component. The angle of dip at this place is …….
Options
(a) 60⁰ (b) 30⁰ (c) 45⁰ (d) […]
The effective length of magnet is 31.4 cm and its pole strength is 0.8Am. The magnetic moment, if it is bent in the form of a semicircle is …….. A-m²
Options
(a) 1.2 (b) […]
If r be the distance of a point on the axis of a magnetic dipole from its centre then the magnetic field at such a point is proportional to
Options
(a) 1/r (b) 1/r² […]
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