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Post your Physics queries here ...

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Ok the ppr is now soo close n v r not even getting any gap ... M quite weak at the energy changes n wud appreciate any help regarding it. Like what r the energy changes in a pendulum, power station n motion of a ball being dropped?
 
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Ok the ppr is now soo close n v r not even getting any gap ... M quite weak at the energy changes n wud appreciate any help regarding it. Like what r the energy changes in a pendulum, power station n motion of a ball being dropped?
Depends on the power station. For fossil fuel/thermal : chemical to kinetic to hear to kinetic in turning turbines and finally into electrical
Hydroelectric: potential into kinetic into electrical
Wind: kinetic into kinetic into electrical
Solar: heat into chemical into electrical

Pendulum: gravitational potential into kinetic into heat
Ball falling: gravitational into kinetic into heat & sound
 
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.. emm can someone explain why electromagnetic waves are easily absorbed when their wavelengths are short and they are at high frequencies.....like Gamma rays ... they are dangerous while radio waves can easily pass through atmosphere without much absorb.... :confused: And there was an mcq on this from some year i cant ... remember...


And have you done Transistors, Bistable and Astable circuits... the optional part of syllabus...
 
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Depends on the power station. For fossil fuel/thermal : chemical to kinetic to hear to kinetic in turning turbines and finally into electrical
Hydroelectric: potential into kinetic into electrical
Wind: kinetic into kinetic into electrical
Solar: heat into chemical into electrical

Pendulum: gravitational potential into kinetic into heat
Ball falling: gravitational into kinetic into heat & sound
Thnx for dat :) also i wanted to know that which energy is greatest at the mid-point of pendulum n at its highest point?
 
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Thnx for dat :) also i wanted to know that which energy is greatest at the mid-point of pendulum n at its highest point?


K.E is greatest at mid point Yes and that point is often taken as reference for No. oscillation experiment ...
 
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.. emm can someone explain why electromagnetic waves are easily absorbed when their wavelengths are short and they are at high frequencies.....like Gamma rays ... they are dangerous while radio waves can easily pass through atmosphere without much absorb.... :confused: And there was an mcq on this from some year i cant ... remember...


And have you done Transistors, Bistable and Astable circuits... the optional part of syllabus...
Bistable and stable? What are those? The logic gates :/
 
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.. emm can someone explain why electromagnetic waves are easily absorbed when their wavelengths are short and they are at high frequencies.....like Gamma rays ... they are dangerous while radio waves can easily pass through atmosphere without much absorb.... :confused: And there was an mcq on this from some year i cant ... remember...


And have you done Transistors, Bistable and Astable circuits... the optional part of syllabus...
For that u have to learn the whole order of spectrum. Waves upwards have low frequencies n larger wavelengths. These r usually harmless as infrared r used in remote controls as well. Waves down have high frequency n short wavelength, which makes them dangerous. These include the gamma rays and ultrasonic waves. I have studied transistors, but bistable n astable :/ never heard of it
 
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can somebody tell me what logic gates are and how they work??
Logic gates r the "ratta wali thing" :p They r the different arrangements of inputs n outputs in a circuit. Three Basic gates r AND, OR, NOT. Other 2 gates r combinations of basic gates. They r NAND n NOR. For more help, try these notes.
 

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whts a relay circuit???
Relay circuit is one in which a small change in current or voltage controls the switching on n off of the circuit or other devices. Circuit breaker is an example of a relay circuit. When current becomes high inside, soft iron bar is magnetised and it attracts the iron armature in the circuit, closing the circuit. A magnetic relay switch is a device used to control a large current output circuit with the help of small current input crcuit. In this also, an electromagnet is used.
 
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Relay circuit is one in which a small change in current or voltage controls the switching on n off of the circuit or other devices. Circuit breaker is an example of a relay circuit. When current becomes high inside, soft iron bar is magnetised and it attracts the iron armature in the circuit, closing the circuit. A magnetic relay switch is a device used to control a large current output circuit with the help of small current input crcuit. In this also, an electromagnet is used.
THNX :)
 
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t
Logic gates r the "ratta wali thing" :p They r the different arrangements of inputs n outputs in a circuit. Three Basic gates r AND, OR, NOT. Other 2 gates r combinations of basic gates. They r NAND n NOR. For more help, try these notes.
thankuuuuu so muchhh :)!!
 
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What's the answer to this? Is it C (the questions from june2009 btw)
 

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