New questions added automatically. Select an answer for immediate feedback and explanations.
Your Score
0/0
Correct answers
#1
By TheQuizWire
•
Hard
•
Fact Checked
•
24 Jan 2026
The square of a planet’s orbital period is proportional to which power of the semi-major axis of its orbit?
💡 Explanation:Kepler's Third Law of Planetary Motion states that the square of a planet's orbital period (T) is directly proportional to the cube (power of 3) of the semi-major axis (a) of its orbit. This is often written as T² ∝ a³.
#2
By TheQuizWire
•
Hard
•
Fact Checked
•
23 Jan 2026
The Second Law of Thermodynamics fundamentally limits the efficiency of which process?
💡 Explanation:The Second Law of Thermodynamics (specifically the Kelvin-Planck statement) states that it is impossible to construct a device that operates in a cycle and produces no effect other than the extraction of heat from a reservoir and the performance of an equivalent amount of work. This fundamentally limits the maximum possible efficiency (Carnot efficiency) for converting heat energy into mechanical work.
#3
By TheQuizWire
•
Easy
•
Fact Checked
•
15 Jan 2026
A 10 Omega resistor carries a 5 A current. What is the circuit’s voltage?
💡 Explanation:According to Ohm's Law, the voltage (V) across a resistor is the product of the current (I) and the resistance (R). The formula is $V = I times R$. Therefore, $V = 5 text{ A} times 10 Omega = 50 text{ Volts}$.
#4
By TheQuizWire
•
Medium
•
Fact Checked
•
08 Jan 2026
An ambulance siren approaches then recedes. What change in sound frequency does a stationary listener detect?
💡 Explanation:The Doppler effect is the change in frequency or wavelength of a wave in relation to an observer who is moving relative to the wave source. When a source (the siren) approaches an observer, the perceived frequency is higher (increased pitch). When the source moves away, the perceived frequency is lower (decreased pitch).
#5
By TheQuizWire
•
Hard
•
Fact Checked
•
08 Jan 2026
If a perfect black body’s absolute temperature is doubled, by what factor does the total energy radiated increase?
💡 Explanation:According to the Stefan-Boltzmann Law, the total energy (or power) radiated per unit area by a black body is directly proportional to the fourth power of its absolute temperature (T): $P propto T^4$. If the temperature is doubled (2T), the new radiated power ($P'$) will be proportional to $(2T)^4$. $P' propto 16T^4$, meaning the radiated energy increases by a factor of 16.
#6
By TheQuizWire
•
Medium
•
Fact Checked
•
02 Jan 2026
The aerodynamic lift on an aircraft wing is primarily explained by which physics principle?
💡 Explanation:Bernoulli's Principle states that an increase in the speed of a fluid occurs simultaneously with a decrease in its static pressure. The curved shape (aerofoil) of an aircraft wing causes air to flow faster over the top surface than the bottom surface, resulting in lower pressure above the wing and higher pressure below. This pressure difference creates the net upward force known as lift. While Newton's Third Law also contributes to the complete explanation (air is deflected downward, so the wing is pushed upward), Bernoulli's principle provides the primary fluid dynamics explanation for the pressure differential created by the wing's geometry.
#7
By TheQuizWire
•
Medium
•
Fact Checked
•
20 Dec 2025
Which fundamental principle states that the total momentum of an isolated system remains constant?
💡 Explanation:The Law of Conservation of Momentum states that if no external forces act on an isolated system, the total linear momentum of the system remains constant. This is a core principle of classical physics.
#8
By TheQuizWire
•
Hard
•
Fact Checked
•
11 Dec 2025
An astronaut travels at $0.8c$. If the time measured on their clock is 3 hours, how much time has passed on Earth?
💡 Explanation:This question applies the concept of time dilation from Special Relativity. The time interval $(Delta t)$ in the stationary frame (Earth) is related to the proper time $(Delta t_0)$ in the moving frame (astronaut) by the formula: $Delta t = Delta t_0 / sqrt{1 - (v/c)^2}$.
Given $Delta t_0 = 3$ hours and $v = 0.8c$, we calculate the Lorentz factor, $gamma = 1 / sqrt{1 - (0.8)^2}$:
$gamma = 1 / sqrt{1 - 0.64} = 1 / sqrt{0.36} = 1 / 0.6 = 5/3 approx 1.667$.
Therefore, $Delta t = 3 times (5/3) = 5$ hours. The observer on Earth measures a longer time interval for the event (time dilation).
#9
By TheQuizWire
•
Medium
•
Fact Checked
•
09 Dec 2025
Which fundamental principle governs the recoil of a gun and the propulsion of a rocket in space?
💡 Explanation:The recoil of a gun and rocket propulsion are classical examples of the Law of Conservation of Linear Momentum. The forward momentum of the ejected mass (bullet or exhaust gases) is equal in magnitude and opposite in direction to the backward momentum (recoil) of the system's main body, ensuring the total momentum of the closed system remains constant.
#10
By TheQuizWire
•
Hard
•
Fact Checked
•
05 Dec 2025
General Relativity describes gravity as a manifestation of what fundamental property of spacetime?
💡 Explanation:General Relativity, published by Albert Einstein in 1916, fundamentally describes gravity not as a force acting between masses (Newton's view), but as the curvature (or geometry) of the four-dimensional fabric of spacetime caused by the presence of mass and energy. Objects then follow the 'straightest' path (geodesics) through this curved spacetime, which we perceive as the effect of gravity. The exchange of gravitons (Option A) is the theoretical description of gravity within the framework of quantum field theory, which is a separate approach from General Relativity.
✅ Why Practice with Our MCQs?
Always Current: Questions generated from today's top news headlines
Exam-Focused: Perfect for competitive exams' current affairs sections
Build Confidence: Regular practice helps identify weak areas
Quick & Convenient: Practice anytime, anywhere on any device
Instant Feedback: Get immediate results with detailed explanations
❓ Frequently Asked Questions
How often are the MCQs updated?
Our quiz is updated multiple times daily with new questions from current events.
Where are these questions sourced from?
Questions are curated from reputable news outlets, focusing on factual information relevant for competitive exams.
Can I practice on mobile devices?
Absolutely! Our platform is fully responsive and works seamlessly on all devices.
