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If x + y = k is normal to y² = 12x, then k=? (1) 3 (2) 6 (3) 9 (4) None of these

Answer: (3) 9 The normal to a parabola is perpendicular to the tangent of the parabola. Also, it will pass through the point of intersection of... View Article

From the below figure which of the following is not the graph of a quadratic polynomial?

A B C D Answer: (D) A quadratic polynomial is a polynomial of degree two, i.e., the highest... View Article

If the earth were to suddenly contract to 1/n^th if its present radius without any change in its mass, the duration of the new day will be nearly (1) 24/n hr (2) 24nhr (3) 24/n²hr (4) 24n²hr

Answer: (3) 24/n2hr Let the Mass aof the earth = M Radius of the earth = R . Time period of rotation of earth (T) = 24h Angular... View Article

The freezer in a refrigerator is located at the top section so that ________. (1) The motor is not heated (2) The heat gained from the environment in high (3) The heat gained from the environment is low (4) The entire chamber of the refrigerator is cooled quickly due to convection

Answer: (4) The entire chamber of the refrigerator is cooled quickly due to convection Freezer is the source for the refrigerator's coldness.... View Article

Which of the following pair of ores cannot be converted into corresponding metals by pyrometallurgy? (1) Ag2S,ZnS (2) Cu2S,HgS (3) MnO2,SnO2 (4) None of this

Answer: (1) Ag2S,ZnS Pyrometallurgy is a branch of extractive metallurgy. It consists of the thermal treatment of minerals and metallurgical... View Article

A car weighing 100 kg is on a slope that makes an angle 30⁰with the horizontal. The component of car’s weight parallel to the slope is (g = 10ms⁻², g = 10ms⁻²) (1) 500 N (2) 1000 N (3) 15000 N (4) 20000 N

Answer: (1) 500 N Scalar and vector quantities are the two types of quantities. Scalar quantities (speed, time, temperature, and mass) are only... View Article

An organic compound undergoes first-order decomposition. The time taken for its decomposition to 1/8 and 1/10 of its initial concentration at t1/8and t1/10 respectively. What is the value of t1/8 /t1/10 × 10? (Consider log102=0.3) (1) 9 (2) 8 (3) 10 (4) 15

Answer:(1) 9 A first-order reaction can be defined as a chemical reaction in which the reaction rate is linearly dependent on the... View Article

Two batteries of different e.m.fs and different internal resistances are connected as shown in the figure below. The voltage across AB in volts is (1) 4 (2) 5 (3) 6 (4) 7

Answer: (2) 5 The positive terminal connects the two cells, which have varying internal resistance. From the higher potential to the lower... View Article

How to find the Least Common Multiple(LCM)?

Answer: Least Common Multiple (LCM) is a way of finding the smallest common multiple between any two numbers or more. A common multiple is a... View Article

The correct value of the gas constant R is close to (1) 0.082litre−atmK (2) 0.082litre−atmK⁻¹mol⁻¹ (3) 0.082litre−atm⁻¹Kmol⁻¹

Answer: (2) (2) 0.082litre−atmK−1mol−1 In physics, the gas constant (R) is defined as the product of pressure and volume. It... View Article

Which of the following series in the spectrum of hydrogen atom lies in the visible region of the electromagnetic spectrum? (1) Paschen series (2) Balmer series (3) Lyman series (4) Brackett series

Answer: (2) Balmer series The Balmer series was discovered during the years 1885, by Johann Balmer. Thus the series is named after him.... View Article

A bird moves with velocity 20ms⁻¹ in a direction making an angle of 60⁰ with the eastern line and 60⁰ with vertical upward. Represent the velocity vector in rectangular form.

Answer: velocity = 20 m/s Eastern angle = 600 Vertical angle = 600 Let α, β and r be the angle substended by the vector V.... View Article

If two coherent light waves produce minima of fifth order, the path dfference between the waves is (1) 5λ (2) 5λ/2 (3) 7λ/2 (4) 9λ/2

Answer: (4) 9λ/2 Given: Two coherent light waves produce minima of fifth order Path difference for destructive order = (2n +... View Article

The areas of two similar triangles ABC and DEF are 144cm² and 81cm², respectively. If the longest side of larger triangle ABC is 36 cm, then the longest side of the smaller triangle DEF is (1) 20 cm (2) 26 cm (3) 27 cm (4) 30 cm

Answer: (3) 27 cm If two triangles are similar, then the ratio of the area of both triangles is proportional to the square of the ratio of their... View Article

A capacitor is charged with a battery and energy stored is U. After disconnecting battery another capacitor is of same capacity is connected in parallel with it. Then energy stored in each capacitor is (1) U/2 (2) U/4 (3) 4U (4) 2U

Answer: (2) U/4 he capacitor is a device in which electrical energy can be stored. It is an arrangement of two-conductor generally carrying... View Article

The product formed in the reaction of SOCl2 with white phosphorus is? (1) PCl3 (2) SO2Cl2 (3) SCl2 (4) POCl3

Answer: (1) PCl3 Phosphorus is found in number of allotropic forms in which well recognised are being black,red and white. White phosphorus... View Article

Which of the following amines can be synthesized by Gabriel phthalimide reaction (1) Neopentylamine (2) n-butylamine (3) Triethylamine (4) t-butylamine

Answer: (2) n-butylamine The phthalimide forms primary amines through nucleophilic substitution with an alkyl halide. Only one carbon and two... View Article

An aeroplane has to go from a point A to Point B, 500km away due 30o East of north. A wind is blowing due north at a speed of 20m/s. The air speed of the plane is 150m/s. Find the directiion in which the pilot should head the plane to reach the point B.

Answer: The vector diagram for various velocities is shown. Vector AC gives velocity of aeroplane relative to quiet air. Vector CB gives... View Article

What happens when some charge is placed on a soap bubble? (1) Its radius decreases (2) Its radius increases (3) The bubble collapses (4) None of these

Answer: 2) Its radius increases When the charge is placed on the soap bubble, every partion of the surface of the soap bubble has the same... View Article

When a low flying aircraft passes overhead, we sometimes notice a slight shaking of the picture on our TV screen .This is because of the direct signal and reflected signal (1) Interference (2) Diffraction (3) Polarisation of direct signal (4) Both (b) and (c)

Answer: (1) Interference When a low flying aircraft passes overhead there is a change in magnetic flux and thus it causes a disturbance in the... View Article

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