EVERYDAY SCIENCE
Download PDF Click here
فری تیاری کیلے Whatsappجوائن کریںClick
here
چار آپشن میں سے کسی ایک پر کلک کرنے سے جواب سرخ ہو جائے گا۔
زمین کی قدیم ترین چٹانوں کی عمر معلوم کرنے کے لیے کون سا آاسوٹوپ تناسب استعمال ہوتا ہے؟
- Carbon-14 to Nitrogen-14
- Potassium-40 to Argon-40
- Uranium-238 to Lead-206
- None of these
اس سوال کو وضاحت کے ساتھ پڑھیں
Explanation
- The age of Earth’s oldest rocks is commonly determined using the Uranium-238 → Lead-206 radioactive decay system.
- Uranium-238 decays very slowly over billions of years.
- This long half-life makes it ideal for dating ancient geological materials.
- It helps scientists estimate Earth’s age (~4.5 billion years).
Last verified on 14-06-2026
فلوروسینٹ لیمپس میں کون سی گیس استعمال ہوتی ہے؟
- Neon
- Xenon
- Argon
- None of these
اس سوال کو وضاحت کے ساتھ پڑھیں
Explanation
- Fluorescent lamps mainly use argon gas (often with a small amount of mercury vapor).
- Electric current excites the gas and produces ultraviolet (UV) light.
- The UV light then hits the phosphor coating inside the tube.
- This coating produces visible light.
- Argon helps in starting and maintaining the discharge.
Last verified on 14-06-2026
بلیک ہولز کے آہستہ آہستہ ختم ہونے کی وضاحت کون سا تصور کرتا ہے؟
- Hawking radiation
- Dark energy repulsion
- Gravitational wave emission
- None of these
اس سوال کو وضاحت کے ساتھ پڑھیں
Explanation
- Black holes may eventually evaporate due to Hawking radiation.
- This is a theoretical process where black holes emit tiny amounts of radiation.
- Over a very long time, they lose mass and energy.
- As mass decreases, the black hole slowly shrinks.
- Eventually, it can completely evaporate.
Last verified on 14-06-2026
ورم ہول کا نظریاتی کام کیا ہوتا ہے؟
- A region where time stops
- A black hole that emits radiation
- A tunnel connecting two distant points in space time
- None of these
اس سوال کو وضاحت کے ساتھ پڑھیں
Explanation
- A wormhole is a theoretical structure that acts as a tunnel connecting two distant points in space-time.
- It is a solution from Einstein’s general relativity equations.
- It could, in theory, allow shortcuts between far parts of the universe.
- It may also connect different times or regions of space.
Last verified on 14-06-2026
بلیک ہول کا شوارزشلڈ رداس کیا ہوتا ہے؟
- The radius of the accretion disk
- The radius at which escape velocity equals the speed of light
- The radius where nuclear fusion stops
- None of these
اس سوال کو وضاحت کے ساتھ پڑھیں
Explanation
- The Schwarzschild radius is the distance from a black hole where the escape velocity becomes equal to the speed of light.
- If an object comes within this radius, even light cannot escape.
- It defines the event horizon of a non-rotating black hole.
- It depends only on the mass of the object.
Last verified on 14-06-2026
دور کی کہکشائیں جتنی زیادہ دور ہوں، اتنی زیادہ تیزی سے دور جاتی کیوں دکھائی دیتی ہیں؟
- Hubble's law
- Newton's law of gravitation
- Doppler effect
- None of these
اس سوال کو وضاحت کے ساتھ پڑھیں
Explanation
- The observation that distant galaxies move away faster is explained by Hubble’s Law.
- It states that the recessional velocity of galaxies is directly proportional to their distance.
- So, the farther a galaxy is, the faster it appears to move away.
- This is evidence that the universe is expanding.
- It is based on redshift observations of light from galaxies.
Last verified on 14-06-2026
ایکو کارڈیوگرافی میں ڈوپلر ایفیکٹ کیسے مدد دیتا ہے؟
- It amplifies sound waves in arteries
- It measures changes in blood pressure
- It detects frequency shifts in ultrasound waves reflected by moving blood
- None of these
اس سوال کو وضاحت کے ساتھ پڑھیں
Explanation
- In echocardiography, the Doppler effect is used to detect frequency changes in ultrasound waves reflected by moving blood.
- When blood flows toward the probe, frequency increases; when it moves away, it decreases.
- These shifts help measure blood flow speed and direction inside the heart.
- It allows doctors to detect blockages and valve problems.
Last verified on 14-06-2026
ایم آر آئی میں مضبوط مقناطیسی میدان کیوں استعمال کیا جاتا ہے؟
- To accelerate electrons in blood
- To align hydrogen nuclei in the body
- To heat tissues for imaging
- None of these
اس سوال کو وضاحت کے ساتھ پڑھیں
Explanation
- MRI uses strong magnetic fields to align hydrogen nuclei (protons) in the body.
- The human body has lots of water, so hydrogen is abundant.
- When aligned, these nuclei respond to radio waves and produce signals.
- These signals are used to create detailed internal body images.
- MRI works without harmful radiation.
Last verified on 14-06-2026
گھومتے ہوئے آئس اسکیٹر کے ہاتھ اندر کرنے سے رفتار کیوں بڑھ جاتی ہے؟
- Increase in torque
- Increase in kinetic energy from muscles
- Conservation of angular momentum
- None of these
اس سوال کو وضاحت کے ساتھ پڑھیں
Explanation
- A spinning ice skater speeds up when pulling arms inward due to conservation of angular momentum.
- When arms are pulled in, the moment of inertia decreases.
- To keep angular momentum constant, angular velocity increases.
- So the skater spins faster without any external force.
- This is a classic example of rotational motion in physics.
Last verified on 14-06-2026
سائیکل چلنے کی حالت میں مستحکم کیوں رہتی ہے لیکن کھڑی ہونے پر آسانی سے گر جاتی ہے؟
- Friction increases at higher
- Gyroscopic effect of rotating wheels
- Air resistance stabilizes motion
- None of these
اس سوال کو وضاحت کے ساتھ پڑھیں
Explanation
- A bicycle stays stable in motion due to the gyroscopic effect of rotating wheels, which resists tilting.
- When the wheels spin, they create angular momentum that keeps the bicycle balanced.
- At rest, there is no rotation, so no gyroscopic stability is produced.
Last verified on 14-06-2026
