Chemistry-
General
Easy
Question
In the thermal power stations, electricity is produced by producing heat energy from the burning of coal. This is an example of ..
- Physical change
- Periodic change
- Desirable change
- All the above
The correct answer is: Desirable change
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Burning of a candle is an example of ..
Burning of a candle is an example of ..
chemistry-General
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A bob attached to a string is held horizontal and released. The tension and vertical distance from point of suspension can be represented by.
A bob attached to a string is held horizontal and released. The tension and vertical distance from point of suspension can be represented by.
physics-General
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A ball whose size is slightly smaller than width of the tube of radius 2.5 m is projected from bottommost point of a smooth tube fixed in a vertical plane with velocity of 10 m/s. If N1 and N2 are the normal reactions exerted by inner side and outer side of the tube on the ball
A ball whose size is slightly smaller than width of the tube of radius 2.5 m is projected from bottommost point of a smooth tube fixed in a vertical plane with velocity of 10 m/s. If N1 and N2 are the normal reactions exerted by inner side and outer side of the tube on the ball
physics-General
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A conical pendulum is moving in a circle with angular velocity was shown. If tension in the string is T, which of following equations are correct ?
A conical pendulum is moving in a circle with angular velocity was shown. If tension in the string is T, which of following equations are correct ?
physics-General
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A pendulum bob is swinging in a vertical plane such that its angular amplitude is less than 900 . At its highest point, the string is cut. Which trajectory is possible for the bob afterwards.
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physics-General
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Block of 1 kg is initially in equilibrium and is hanging by two identical springs A and B as shown in figures. If spring A is cut from lower point at t=0 then, find acceleration of block in ms–2 at t = 0.
Block of 1 kg is initially in equilibrium and is hanging by two identical springs A and B as shown in figures. If spring A is cut from lower point at t=0 then, find acceleration of block in ms–2 at t = 0.
physics-General
physics-
Find the acceleration of 3 kg mass when acceleration of 2 kg mass is 2 ms–2 as shown in figure.
Find the acceleration of 3 kg mass when acceleration of 2 kg mass is 2 ms–2 as shown in figure.
physics-General
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A rope of mass 5 kg is moving vertically in vertical position with an upwards force of 100 N acting at the upper end and a downwards force of 70 N acting at the lower end. The tension at midpoint of the rope is
A rope of mass 5 kg is moving vertically in vertical position with an upwards force of 100 N acting at the upper end and a downwards force of 70 N acting at the lower end. The tension at midpoint of the rope is
physics-General
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A ball is hit by a batsman at an angle of 37° as shown in figure. The man standing at P should run at what minimum velocity so that he catches the ball before it strikes the ground. Assume that height of man is negligible in comparison to maximum height of projectile.
A ball is hit by a batsman at an angle of 37° as shown in figure. The man standing at P should run at what minimum velocity so that he catches the ball before it strikes the ground. Assume that height of man is negligible in comparison to maximum height of projectile.
physics-General
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Average velocity of a particle is projectile motion between its starting point and the highest point of its trajectory is : (projection speed = u, angle of projection from horizontal= 
)
Average velocity of a particle is projectile motion between its starting point and the highest point of its trajectory is : (projection speed = u, angle of projection from horizontal= )
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If force F is increasing with time and at t = 0 , F = 0 where will slipping first start?
If force F is increasing with time and at t = 0 , F = 0 where will slipping first start?
physics-General
physics-
To paint the side of a building, painter normally hoists himself up by pulling on the rope A as in figure. The painter and platform together weigh 200N. The rope B can withstand 300N. Then
To paint the side of a building, painter normally hoists himself up by pulling on the rope A as in figure. The painter and platform together weigh 200N. The rope B can withstand 300N. Then
physics-General
physics-
An object comprises of a uniform ring of radius R and its uniform chord AB (not necessarily made of the same material) as shown. Which of the following can not be the centre of mass of the object
An object comprises of a uniform ring of radius R and its uniform chord AB (not necessarily made of the same material) as shown. Which of the following can not be the centre of mass of the object
physics-General
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As shown in the figure a body of mass m moving vertically with speed 3 m/s hits a smooth fixed inclined plane and rebounds with a velocity vf in the horizontal direction. If 
of inclined is 30°, the velocity vf will be
As shown in the figure a body of mass m moving vertically with speed 3 m/s hits a smooth fixed inclined plane and rebounds with a velocity vf in the horizontal direction. If of inclined is 30°, the velocity vf will be
physics-General
physics-
A man is crossing a river flowing with velocity of 5 m/s. He reaches a point directly across at a distance of 60 m in 5 sec. His velocity in still water should be
A man is crossing a river flowing with velocity of 5 m/s. He reaches a point directly across at a distance of 60 m in 5 sec. His velocity in still water should be
physics-General
