- AAll substances.
- BSome substances.
- COnly ferromagnetic substances.
- DNone of these options.
Explanation:
A permanent magnet has the capacity to attract only ferromagnetic substances.
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A convex lens of power + 6D is placed in contact with a concave lens of power – 4D. What is the nature and focal length of the combination
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(a) Concave, 25 cm |
(b) Convex, 50 cm |
(c) Concave, 20 cm |
(d) Convex, 100 cm |
Two long wires are hanging freely. They are joined first in parallel and then in series and then are connected with a battery. In both cases, which type of force acts between the two wires
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(a) Attraction force when in parallel and repulsion force when in series |
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(b) Repulsion force when in parallel and attraction force when in series |
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(c) Repulsion force in both cases |
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(d) Attraction force in both cases |
A radioactive nucleus emits a beta particle. The parent and daughter nuclei are
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(a) Isotopes |
(b) Isotones |
(c) Isomers |
(d) Isobars |
Assertion : For a perfectly diamagnetic substance permeability is always one.
Reason : The ability of a material of permit the passage of magnetic lines of force through it is called magnetic permeability.
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(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
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(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
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(c) If assertion is true but reason is false. |
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(d) If assertion is false but reason is true. |