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Pusa A-4 is resistant to shoot and fruit borer.

A) True B) False Answer:A) True Explanation:Pusa A-4 is an insect-resistant variety of okra or bhindi. It is resistant to shoot and fruit... View Article

Is the sunflower an example of cypsela?

Answer: Yes, the fruit of the sunflower is a cypsela. It is the characteristic of the Asteraceae family Further reading: Endosperm Racemose... View Article

Fascicular cambium found in dicot stem is a

1) Primary meristem 2) Intercalary meristem 3) Lateral meristem 4) Apical meristem Answer:3) Lateral meristem Explanation: Fascicular meristem is... View Article

In prokaryotes ribosomes are attached to

Answer: plasma membrane Explanation: In prokaryotes, ribosomes are attached to the plasma membrane. They are made up of two subunits 50S and 30S,... View Article

A particle is revolving in a circle with increasing its speed uniformly. Which of the following is constant ?

a) centripetal acceleration b) tangential acceleration c) angular acceleration d) None of these Answer: c) angular acceleration... View Article

A source of light is located at double focal length from a convergent lens. The focal length of the lens is f=30cm. At what distance from the lens should a flat mirror be placed so that the rays reflected from the mirror are parallel after passing through the lens for the second time?

Answer: 45 cm Solution: The mirror should be placed at (f + f/2) distance 30cm+ (30/2) cm = 45cm from light sides of the lens.... View Article

If a man’s face is 25 cm in front of a concave shaving mirror producing an erect image 1.5 times the size of the face, the focal length of the mirror would be a) 75 cm b) 25 cm c) 15 cm d) 60 cm

Answer: a) 75 cm Solution: In concave shaving mirror m =-(v/u) ⇒ 1.5 = -v/-25 v = (75/2) cm (1/f) = (1/v) + (1/u) = (2/75) + (1/-25) =... View Article

Two charges each equal to q, are kept at x = -a and x = a on the x-axis. A particle of mass m and charge q₀ = q/2 is placed at the origin. If charge q₀ is given, a small displacement (y << a) along the y-axis, the net force acting on the particle is proportional to

a) y b) -y c) 1/y d) -1/y Answer: a) y Solution: From Coulomb's law F = kq(q/2)/r2 k = Coulomb's constant r is the distance between... View Article

Four identical copper cylinders are painted. If they are all heated to the same temperature and left in the vacuum which will cool most rapidly?

a) the one painted shiny white b) the one painted rough black c) the one painted shiny black d) the one painted rough white... View Article

The value of angle of dip is zero at the magnetic equator because on it:

a) V and H are equal b) V and H are zero c) V is zero d) V is infinity Answer: c) V is zero Solution: Angle of... View Article

A 2kg mass moving with a velocity of 3 m/sec collides head-on with a body of mass 1 kg moving in the opposite direction with a velocity of 4 m/sec. After the collision, two bodies stick together and move with a common velocity which in m/sec is equal to

a) 1/4 b) 1/3 c) 2/3 d) 3/4 Answer: c) 2/3 Solution: After the collision, the two bodies stick together and move with a common... View Article

The reading of ammeter and voltmeter in the following circuit are respectively

a) 2 A, 200 V b) 1.5 A, 100 V c) 2.7 A, 220 V d) 2.2 A, 220 V Answer: a) 2 A, 200 V Solution: VR = 200 I = VR/R = 200/100 = 2 A... View Article

A spring of spring constant k is placed horizontally on a rough horizontal surface. It is compressed against a block of mass m which is placed on the rough surface, so as to store maximum energy in the spring. If the coefficient of friction between the block and the surface is μ, the potential energy stored to the spring is: (block does not slide due to force of spring.)

a) μ2m2g2/4k b) 2μm2g2/k c) μ2m2g2/2k d) 3μ2mg2/k Answer: c) μ2m2g2/2k Solution: Maximum energy is... View Article

[latex]vec{A}[/latex] and [latex]vec{B}[/latex] are two vectors and θ is the angle between them, if
[latex]left|vec{A}times vec{B} right|=sqrt{3}(vec{A}vec{B})[/latex] the value of θ is

a) 600 b) 450 c) 300 d) 900 Answer: Solution: tan θ = √3 ⇒ θ = 600... View Article

If the system is in equilibrium (cos53⁰= 3/5), then the value of P is

a) 16 N b) 4 N c) √208 N d) √232 N Answer: c) √208 N Solution: As the system is in equilibrium, the sum of all vector forces will be zero.... View Article

Why is the lunar eclipse not visible in all the places on the night side of the earth?

The lunar eclipse occurs if the Sun, the Earth and the Moon are totally or very closely aligned with the Earth between the Sun and Moon. If you... View Article

A tunnel through a mountain for a four-lane highway is to have an elliptical opening. The total width of the highway (not the opening) is to be 16m, and the height at the edge of the road must be sufficient for a truck 4m high to clear if the highest point of the opening is to be 5m approximately. How wide must the opening be

Answer: Solution: AA' = 16 m OA = 8 cm OB = 5m Equation of ellipse = (x2/82) + (y2/52) = 1 Substituting (x1,4) in equation (1) (x12/82)... View Article

The current sensitivity of a moving coil galvanometer can be increased bya) Increasing the magnetic field of the permanent magnet b) Increasing the area of the deflecting coil c) Increasing the number of turns in the coil d) Increasing the restoring couple of the coil

The correct options are (a) , (b) and (c) Current sensitivity of the moving coil galvanometer = Current sensitivity of the moving coil... View Article

Increasing the current sensitivity of a galvanometer may not necessarily increase its voltage sensitivity. Give reasons

Solution: Current sensitivity of the moving coil galvanometer = nBA/k here n = number of turns A= area of the coil B = magnetic field... View Article

Calculate the binding energy and binding energy per nucleon (in MeV) of a nitrogen nucleus (7N14) from the following data : Mass of proton = 1.00783 u, Mass of neutron = 1.00867 u, Mass of nitrogen nucleus = 14.00307 u

Solution In 14N7 : Number of protons = 7, Number of neutron = 7 Total number of nucleons = 7 +7 =14 Mass defect (ΔM) =7 (mass of proton) +... View Article

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