computer science
What is an algorithm?
A step-by-step set of instructions to solve a problem or perform a task.
What is the main language spoken in Brazil?
Portuguese
This particle is the gauge boson responsible for mediating the electromagnetic force.
What is the photon?
This is the only country in the world that is also a continent.
What is Australia?
his ancient empire was ruled by Cyrus the Great and later by Darius I, stretching from the Balkans to the Indus Valley.
What is the Achaemenid Empire (Persian Empire)?
What is the difference between a stack and a queue?
A stack is LIFO (Last In, First Out) — like a pile of plates.
A queue is FIFO (First In, First Out) — like a line at a store.
Which African country has three capital cities, and what are they?
South Africa — Pretoria (executive), Cape Town (legislative), Bloemfontein (judicial)
What is the speed of light in a vacuum, approximately?
299,792,458
This mountain range forms a natural border between France and Spain.
What are the Pyrenees?
This treaty officially ended World War I and imposed heavy reparations on Germany.
What is the Treaty of Versailles?
What are the key differences between monolithic and microservices architectures, and what trade-offs do they present?
Monolithic apps are single units; easier to develop initially but hard to scale/maintain. Microservices split the app into services; better scalability and modularity, but add complexity in communication, deployment, and testing.
What gas do plants primarily absorb from the atmosphere for photosynthesis?
Carbon dioxide (CO₂)
This theoretical concept implies that energy density of empty space has gravitational effects, possibly explaining the accelerated expansion of the universe.
What is dark energy?
This island country is located in the Indian Ocean, southeast of India, and is famous for its tea plantations.
What is Sri Lanka?
The Battle of Hastings in 1066 led to the Norman conquest of England. Who led the Normans?
Who is William the Conqueror?
Explain the difference between a process and a thread. How does context switching differ between them?
A process is an independent program with its own memory. A thread is a lightweight sub-unit of a process sharing memory. Context switching between processes is heavier (switching memory contexts), while thread switching is faster since memory is shared.
What is the capital of the country with the most islands in the world?
Stockholm
Consider a black hole of mass M and radius Rs (the Schwarzschild radius). An object of mass mmm is in a stable orbit just above the event horizon of the black hole. Derive the escape velocity at this orbit and explain why this velocity is equal to the speed of light at the event horizon.
haci aga bunu tapsa molodes ne deyim vallah :=(
Escape Velocity
At the Event Horizon
Escape Velocity at the Event Horizon
(dustur bura girmedi)
This city is home to the oldest active university in the world, founded in 859 AD.
What is Fez (in Morocco)?
The ancient city of Carthage, a rival to Rome, was located in which modern-day country?
What is Tunisia?
What is the difference between deterministic and non-deterministic polynomial time, and why is the P vs NP problem considered one of the greatest unsolved problems in computer science?
herseyi demelisiz!1!1!11
P (Polynomial time): Class of problems solvable in polynomial time by a deterministic Turing machine — i.e., efficiently solvable.
NP (Non-deterministic Polynomial time): Class of problems where a proposed solution can be verified in polynomial time — even if we don’t know how to find it efficiently. These include things like the traveling salesman, boolean satisfiability, etc.
The P vs NP question asks:
"If a solution can be quickly verified, can it also be quickly found?"
If P = NP, it would mean all problems whose answers we can verify quickly, we can also solve quickly. That would upend cryptography, optimization, AI... basically modern life.
If P ≠ NP, then there exist problems where verifying is easy, but solving is fundamentally hard — meaning there are limits to what computers can ever efficiently compute.
What was the first artificial Earth satellite, and who launched it?
Sputnik 1, launched by the Soviet Union (USSR) in 1957
Consider two particles, one with mass m1 and the other with mass m2, separated by a distance r Derive the expression for the gravitational potential energy of the system and explain how this energy would change if one of the particles were to move closer to the other at a relativistic speed (close to the speed of light). How does this affect the energy from a relativistic viewpoint?
Gravitational Potential Energy (Classical):
For two masses, m1m_1m1 and m2m_2m2, separated by a distance rrr, the gravitational potential energy UUU is given by the classical equation:
U=−Gm1m2rU = - \frac{G m_1 m_2}{r}U=−rGm1m2
Where:
GGG is the gravitational constant,
m1m_1m1 and m2m_2m2 are the masses of the two objects,
rrr is the distance between them.
2.Effect of a Relativistic Speed:
When one of the particles moves at relativistic speeds (near the speed of light), we need to account for relativistic effects. Classical physics alone won't be enough because relativity changes our understanding of both energy and gravity.
In relativity, energy is conserved, but the total energy includes both kinetic energy and rest energy. The relativistic kinetic energy is given by:
Where:
γ=11−v2/c2\gamma = \frac{1}{\sqrt{1 - v^2/c^2}}γ=1−v2/c21 is the Lorentz factor,
vvv is the speed of the moving particle,
ccc is the speed of light,
mmm is the mass of the moving object.
This energy increases significantly as the speed approaches the speed of light.
Relativistic Gravitational Energy:
To fully describe the gravitational potential energy in a relativistic context, we must consider that gravity itself becomes affected by relativistic speeds. Specifically, the gravitational field is non-static and dynamic in relativity, which means the curvature of spacetime needs to be accounted for, especially at high speeds or near massive objects.
At relativistic speeds, the gravitational potential energy should still follow the classical formula for large distances, but the dynamics of spacetime (how mass distorts space) must be considered for more accurate modeling (such as in General Relativity). In some extreme cases (like near black holes), energy in gravitational fields becomes more complex to compute due to the warping of spacetime.
Classical energy: The potential energy between two masses m1m_1m1 and m2m_2m2 at distance rrr is U=−Gm1m2rU = - \frac{G m_1 m_2}{r}U=−rGm1m2.
Relativistic energy: When one particle moves at relativistic speeds, its kinetic energy increases dramatically as its velocity approaches the speed of light, affecting the total energy of the system.
The gravitational energy doesn’t fundamentally change unless we move to extremely high masses or speeds, but relativity modifies the dynamics of gravitational fields (especially in high-gravity environments like near black holes or neutron stars).
This is the only place on Earth where four countries meet at a single geographic point — a quadripoint.
What is the Kazungula Quadripoint (Botswana, Namibia, Zambia, and Zimbabwe — though it's debated due to a narrow river border)?
During the Thirty Years’ War, this Bohemian event triggered the conflict by throwing Catholic officials out a castle window.
What is the Defenestration of Prague?