Class 12 | Biology | chapter 14 | Ecosystem

What do you mean by Productivity? 1. Rate of biomass production 2. Amount of biomass production 3. Biomass produced in an area 4. Biomass produced in a time period

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Class 12 | Biology | chapter 14 | Ecosystem

Q. What is the annual net primary productivity of the whole biosphere 1. 160 billion tons 2. 170 billion tons 3. 177 billion tons 4. 190 billion tons Ans:2. 170 billion tons

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Class 12 | Biology | chapter 14 | Ecosystem

Q Which of the following contributes the maximum to the net primary productivity? 1. Ocean ecosystem 2. Land ecosystem 3. Pond ecosystem 4. Man-made ecosystem Ans:2. Land ecosystem

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Class 12 | Biology | chapter 14 | Ecosystem

Identify the odd one out? 1. Forest 2. Grassland 3. Desert 4. Wetland

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Kinetic Energy

A body of mass (4m) is lying in x-y plane at rest. It suddenly explodes into three pieces. Two pieces, each of mass (m) move perpendicular to each other with equal speeds (v). The total kinetic energy generated due to explosion is

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Kinetic Energy

Before a rubber ball bounces off from the floor, the ball is in contact with the floor for a fraction of second. Which of the following statements is correct? (a) Conservation of energy is not valid during this period (b) Conservation of energy is valid during this period (c) As ball is compressed, kinetic energy is converted to compressed potential energy (d) None of these

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Kinetic Energy

A particle moves in a straight line with retardation proportional to its displacement. Its loss of kinetic energy for any displacement x is proportional to

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Kinetic Energy

An electron and a proton are moving under the influence of mutual forces. In calculating the change in the kinetic energy of the system during motion, one ignores the magnetic force of one on another. This is because, (a) the two magnetic forces are equal and opposite, so they produce no net effect. (b) the magnetic forces do no work on each particle. (c) the magnetic forces do equal and opposite (but nonzero) work on each particle. (d) the magnetic forces are necessarily negligible.

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Kinetic Energy

At time t = 0s particle starts moving along the x-axis. If its kinetic energy increases uniformly with time t, the net force acting on it must be proportional to

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Kinetic Energy

Kinetic energy, with any reference, must be (a) zero (b) positive (c) negative (d) both (b) and (c)

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Kinetic Energy

According to work-energy theorem, the work done by the net force on a particle is equal to the change in its (a) kinetic energy (b) potential energy (c) linear momentum (d) angular momentum

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Kinetic Energy

In an explosion, a body breaks up into two pieces of unequal masses. In this (a) both parts will have numerically equal momentum (b) lighter part will have more momentum (c) heavier part will have more momentum (d) both parts will have equal kinetic energy

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Rapid Revision & Formula Bank Physics 11th

CLASS 11 | Physics |CHAPTER 5 | Laws of Motion,Rapid Revision & Formula Bank

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Kinetic Energy

A cricket ball is hit at an angle of 30° to the horizontal with a kinetic energy E. Its kinetic energy when it reaches the highest point is (a) E/2 (b) 0 (c) 2E/3 (d) 3E/4

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Kinetic Energy

A ball is thrown upwards and it returns to ground describing a parabolic path. Which of the following has the same value at the time of throw and the time of return? I. Kinetic energy of the ball II. Speed of the ball III. Vertical component of velocity (a) I and II (b) II and III (c) III only (d) I, II and III

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Rapid Revision & Formula Bank Physics 11th

CLASS 11 | Physics |CHAPTER 4 | Motion In A Plane,Rapid Revision & Formula Bank

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MindMap Physics

CLASS 11 | Physics |CHAPTER 4 | Motion In A Plane,MindMap

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Class 12 | Physics | Chapter 12 | Atoms

A body of mass m moves in a circular path with uniform angular velocity. The motion of the body has constant (a) acceleration (b) velocity (c) momentum (d) kinetic energy

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