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
-
Two springs of force constants k₁ and k₂ are joined in series. The effective force constant is:
सही उत्तर: क) k₁k₂/(k₁ + k₂)
In series the same force acts on both and the extensions add: 1/k = 1/k₁ + 1/k₂, so k = k₁k₂/(k₁ + k₂).
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
For small oscillations, the time period of a simple pendulum:
सही उत्तर: घ) is independent of the mass of the bob
T = 2π√(l/g) contains no mass term, so the period does not depend on the mass of the bob.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
A geostationary satellite orbits at a height above the Earth's surface of about:
सही उत्तर: ग) 36,000 km
A 24 h orbital period requires an orbital radius of about 42,000 km, i.e. a height of about 36,000 km above the surface.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
For a satellite in a circular orbit, the ratio of its kinetic energy to the magnitude of its gravitational potential energy is:
सही उत्तर: ख) 1 : 2
K = GMm/(2r) and |U| = GMm/r, so K : |U| = 1 : 2.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
Due to the rotation and shape of the Earth, the value of g at sea level is maximum at the:
सही उत्तर: क) poles
At the poles the centrifugal effect is zero and the distance from the centre is least, so g is greatest.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
A planet has twice the mass and twice the radius of the Earth. The acceleration due to gravity on its surface is (g = value on Earth):
सही उत्तर: घ) g/2
g = GM/R²; doubling M and R gives g′ = 2/4 × g = g/2.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The gravitational potential at the surface of the Earth (mass M, radius R) is:
सही उत्तर: ग) −GM/R
Gravitational potential due to a spherical mass at distance r ≥ R is V = −GM/r, so at the surface V = −GM/R.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
If the distance between two point masses is tripled, the gravitational force between them becomes:
सही उत्तर: ख) 1/9 of the original
F ∝ 1/r², so tripling r reduces F to 1/9.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The centre of mass of a thin uniform semicircular ring (wire) of radius R lies on its symmetry axis at a distance from the centre equal to:
सही उत्तर: क) 2R/π
For a semicircular wire, y_cm = (1/πR)∫R sin θ · R dθ from 0 to π = 2R/π; 4R/3π is for a semicircular disc.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
A body rotating freely changes its moment of inertia to half its value while its angular momentum stays constant. Its rotational kinetic energy becomes:
सही उत्तर: घ) double
K = L²/(2I); with L constant, halving I doubles K.
💬 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।