In solar devices, the energy is concentrated into a small area using
A) plane mirror
B) concave mirror
C) parabolic mirror
D) parabolic or concave mirror
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The total surface area of solid cylinder is `231 cm^(2)` and its curved surface area is `(2)/(3)` of the total surface area. Find the volume of the cy
Correct Answer - `269.5 cm^(3)`
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The correct statement related to autotrophs A) getting mechanical energy from solar energy
C) converts solar energy into chemical energy
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Write a note on: i. Electric devices ii. Electronic devices
i. Electric devices: 1. These devices convert electrical energy into some other form. 2. Examples: Fan, refrigerator, geyser etc. Fan converts electrical energy into mechanical energy. A geyser converts it into heat...
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Which of the following can convert the absorbed (Solar energy) sunlight into chemical energy ?
C) Producers
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Pressure = ………… A) Force B) Force x area C) Area / force D) Force / area
D) Force / area
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Which of the following is said to be the brain of a computer? (a) Input devices (b) Output devices (c) Memory device (d) Microprocessor
(d) Microprocessor
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Assertion (A): Nitration of benzene with nitric acid requires the use of concentrated sulphuric acid. Reason (R):The mixture of concentrated sulphuric
Both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
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List two forms of energy in which solar energy manifests itself in oceans.
Tidal energy and Sea-wave energy.
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List two indirect ways of using Solar energy.
(i) Wind energy (ii) Biomass energy
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When a metal rod M is dipped into an aqueous colourless concentrated solution of compound N, the solution turns light blue. Addition of aqueous NaCl t
Correct Answer - B `underset((M))(Cu)+underset((N))(2AgNO_(3))rarrunderset(("Blue"))(Cu(NO_(3))_(2))+2Ag` `NaCl+underset(("remaining"))(AgNO_(3))rarrunderset((O))(AgCldarr)+NaNO_(3)` `2AgCl+2NH_(3)(aq)rarrunderset(("Soluble"))([Ag(NH_(3))_(2)]^(+))` `underset(("remaining"))(Cu(NO_(3))_(2))+4NH_(3)(aq)rarrunderset(("Deep blue colour"))([Cu(NH_(3))_(4)](NO_(3))_(2))`
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