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Fill in the blanks with most appropriate option.
Bio-gas is an excellent fuel as it contains up to 75% __(i)__ . It burns without smoke, leaves no residue like ash in wood. Its heating capacity is __(ii)__ . The slurry left behind is removed periodically and used as excellent manure, rich in __(iii)__and __(iv)__.

Which of the following statements are correct?
(i) The glass sheet in a solar cooker is responsible for green house effect.
(ii) Acid rain happens because earth’s atmosphere contains acids.
(iii) Biomass is a renewable source of energy.
(iv) Non-conventional sources of energy are nuclear, solar, biomass etc.
(v) Sun can be taken as inexhaustible source of energy.

A(i) and (iv) only
B (ii) and (iii) only
C (iii), (iv) and (v) only
D (i), (iii) and (v) only

A wire of resistance 4 Ω is used to wind a coil of radius 7 cm. The wire has a diameter of 1.4 mm and the specific resistance of its material is 2 × 10^-7 Ω m. The number of turns in the coil is

A 50
B 40
C 60
D 70

A wire of resistance 5 Ω is bent into a circular loop and the resistance between its diametrically opposite points is measured to be R. Now, it is stretched so that its length is increased by twice its original. Again, it is bent into a bigger circular loop and the resistance between its diametrically opposite points is measured to be R'. Then R : R' will be

A 1 : 4
B 9 : 1
C 1 : 9
D 1 : 1

Refer to the given pedigree chart showing inheritance of fused ear lobe trait in three generations of a family. Select the option that correctly depicts the genotypes of I-2, II-4 and III-2.


A
B
C
D

An electric current passes through a straight wire. Magnetic compasses are placed at the points X and Y.


A Their needles will not deflect.
B Only one of the needles will deflect.
C The needles will deflect in the same direction.
D The needles will deflect in the opposite directions.

Three closed similar coils P, Q and R are placed such that their planes are parallel. In the coil P and R, current of same magnitude flows as shown in the figure. Coils Q and R are static while coil P is moved with a uniform speed towards Q, then


A Clockwise current will be induced in coil Q, as seen by eye
B Anti-clockwise current will be induced in coil Q, as seen by eye.
C No current will flow in coil Q
D Current induced in coil Q will be equal to P and R, but in opposite direction, hence net current in Q will be zero.