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چار آپشن میں سے کسی ایک پر کلک کرنے سے جواب سرخ ہو جائے گا۔
جس عمل میں دباؤ مستقل رہتا ہے اسے ______ کہا جاتا ہے؟
Isobaric
Isothermal
Adiabatic
None of these
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Explanation
“Iso-” means constant; “baric ” relates to pressure .
In an isobaric process , pressure remains unchanged .
Volume or temperature can change during the process.
Examples: heating a gas in a piston-cylinder system a t constant atmospheric pressure.
Isochoric = constant volume, isothermal = constant temperature, adiabatic = no heat transfer.
Last updated question 25 feb 2026
Pressure
Work done
Internal energy
Imaginary number
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Explanation
In an isothermal process, the temperature remains constant , so the internal energy of an ideal gas also remains constant.
اینٹروپی میں تبدیلی _____ کے لئے صفر ہے؟
Reversible isobaric processes
Reversible adiabatic processes
Reversible isothermal processes
None of these
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Explanation
In a reversible adiabatic process , no heat is exchanged with the surroundings ( Q = 0 ), so the change in entropy (ΔS ) is zero. Entropy change is linked to heat transfer, and since no heat enters or leaves, entropy remains constant.
Giant
Speck
Heap
Chunk
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Explanation
Mite مائیٹ
Speck سپیک
جب روشنی خلا سے شیشے میں داخل ہوتی ہے تو اس کی رفتار؟
Decreases
Remains same results
Increases
Varies depending on mass of glass
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Explanation
When light enters from a vacuum into glass, its velocity decreases . This is because light travels at a speed of approximately 299,792,458 meters per second (m/s) in a vacuum, but it travels at a slower speed in a medium with a higher refractive index, such as glass.
Emitter
Base
Collector
Anyone can be heavily doped
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Explanation
The heavily doped region of a transistor is called the emitter .
The emitter's heavy doping ensures it injects a large number of charge carriers (electrons in NPN transistors, holes in PNP transistors) into the base region, which is crucial for the transistor's operation.
Isaac Newton
James Clerk Maxwell
Albert Einstein
Niels Bohr
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Explanation
Albert Einstein explained the photoelectric effect in 1905,
Showing that light consists of particles (photons),
This work earned him the Nobel Prize in Physics in 1921.
1
2
3
4
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Explanation
A NOT gate has only one input.
A NOT gate, also known as an inverter.
It is a digital logic gate that negates the input signal.
If the input is "1", the output will be "0".
If the input is "0", the output will be "1".
The truth table for a NOT gate is:
Input | Output
-----|------
0 | 1
1 | 0
Fire
Oven
Flue
Stove
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Explanation
- Tobacco passes t hrough a pipe, and
Similarly
Smoke from burning coal passes through a flue (a duct or pipe for conveying exhaust gases).
- Both are passageways for smoke or fumes.
گاما کرنوں میں _____ پر مشتمل ہے؟
Helium nuclei
Neutrons
Radiations similar to x-rays
None of these
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Explanation
Gamma rays consist of radiations similar to x-rays.
They are high-energy electromagnetic waves with no mass or charge.
