भौतिक विज्ञान (Physics) – Physics MCQ
भौतिक विज्ञान (Physics) – इन्जिनियरिङ प्रवेश
Physics · Engineering Entrance – Mathematics, Physics, Chemistry & English · १,३९८ प्रश्न
१,३९८ प्रश्न उपलब्ध। मोड छान्नुहोस्:
भौतिक विज्ञान (Physics): प्रश्न र उत्तर
सही लागेको विकल्पमा थिच्नुहोस्। सही भए हरियो, गलत भए रातो देखिन्छ; ३ सेकेन्डपछि सही उत्तर र व्याख्या देखिन्छ।
सही: ० / ०
-
Kepler's second law (law of areas) is a consequence of conservation of:
सही उत्तर: क) Angular momentum
Gravity is a central force, so it exerts no torque about the Sun; angular momentum is conserved, which means equal areas are swept in equal times.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The time period of a geostationary satellite is:
सही उत्तर: घ) 24 hours
A geostationary satellite rotates with the Earth in the equatorial plane, so its period equals Earth's rotation period of about 24 hours. Hence it appears fixed in the sky.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The acceleration due to gravity at a depth of R/2 below the Earth's surface (R = radius of Earth) is:
सही उत्तर: ग) g/2
Inside a uniform Earth, g' = g(1 − d/R) = g(1 − 1/2) = g/2. g becomes zero only at the centre.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The acceleration due to gravity at a height equal to the Earth's radius R above the surface is:
सही उत्तर: ख) g/4
g' = g R²/(R + h)² = g R²/(2R)² = g/4. g/2 is a common mistake from treating g as inversely proportional to distance.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
Torque is the rotational analogue of:
सही उत्तर: क) Force
Torque causes angular acceleration just as force causes linear acceleration (τ = Iα vs F = ma). Moment of inertia is the analogue of mass.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
A ring, a disc, a hollow sphere and a solid sphere of the same mass and radius roll down the same incline from rest. Which reaches the bottom first?
सही उत्तर: घ) Solid sphere
Acceleration = g sinθ/(1 + K²/R²); the solid sphere has the smallest K²/R² (2/5), so it is fastest. The ring (K²/R² = 1) is slowest.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The radius of gyration of a uniform disc of radius R about an axis through its centre and perpendicular to its plane is:
सही उत्तर: ग) R/√2
I = MR²/2 = MK², so K = R/√2. K = R would apply to a ring.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
An ice skater spinning with arms outstretched pulls her arms in. Her angular velocity:
सही उत्तर: ख) Increases
With no external torque, angular momentum Iω is conserved. Pulling arms in reduces I, so ω increases.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The moment of inertia of a thin ring of mass M and radius R about an axis through its centre and perpendicular to its plane is:
सही उत्तर: क) MR²
All the mass of a ring lies at distance R from the axis, so I = MR². MR²/2 is for a uniform disc about the same axis.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The work–energy theorem states that the work done by the net force on a body equals the change in its:
सही उत्तर: घ) Kinetic energy
W_net = ΔK for any type of force. Change in momentum equals impulse, not work.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
यी अभ्यास प्रश्न हुन्, आधिकारिक प्रश्न होइनन्। पाठ्यक्रम, विज्ञापन र नतिजाका लागि सम्बन्धित निकायको आधिकारिक वेबसाइट हेर्नुहोस्। उत्तरमा गल्ती भेटे प्रश्नमुनिको "टिप्पणी / गल्ती रिपोर्ट" मा लेख्नुहोस्।
नमस्ते! पाठ्यक्रम, सामान्य ज्ञान, भाषा परीक्षा वा कुनै प्रश्नको उत्तर बुझ्न सोध्नुहोस्।
AI ले गल्ती गर्न सक्छ। महत्वपूर्ण कुरा आधिकारिक स्रोतमा जाँच्नुहोस्।