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
-
A coil of 100 turns and area 0.01 m² carries 0.5 A in a uniform field of 0.2 T, with the plane of the coil parallel to the field. The torque on it is:
सही उत्तर: घ) 0.1 N m
With the plane parallel to B, the angle between the area vector and B is 90°: τ = NIAB = 100 × 0.5 × 0.01 × 0.2 = 0.1 N m.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The magnetic field at the centre of a square loop of side a carrying current I is:
सही उत्तर: ख) 2√2 μ₀I/(πa)
Each side gives μ₀I/(4π(a/2)) × 2 sin 45° = √2μ₀I/(2πa); four sides give 2√2 μ₀I/(πa).
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
An ammeter of resistance 0.9 Ω reads up to 1 A. When a 0.1 Ω shunt is connected across it, its range becomes:
सही उत्तर: घ) 10 A
I = I_g(1 + G/S) = 1 × (1 + 0.9/0.1) = 10 A.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
In a potentiometer, a standard cell of emf 1.5 V balances at 300 cm. Another cell balances at 400 cm. Its emf is:
सही उत्तर: क) 2 V
E ∝ balancing length: E₂ = 1.5 × 400/300 = 2 V.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
Cells of emf 2 V (internal resistance 1 Ω) and 4 V (internal resistance 2 Ω) are connected in parallel with like terminals together. The emf of the equivalent cell is:
सही उत्तर: ग) 8/3 V
E_eq = (E₁/r₁ + E₂/r₂)/(1/r₁ + 1/r₂) = (2 + 2)/(1.5) = 8/3 V.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
Five 100 W bulbs are used for 6 hours a day for 30 days. At Rs 10 per unit (kWh), the cost of energy is:
सही उत्तर: घ) Rs 900
Energy = 0.5 kW × 6 h × 30 = 90 kWh; cost = 90 × 10 = Rs 900.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
An electric heater rated 1000 W at 220 V is operated on 110 V. Assuming its resistance stays constant, its power is:
सही उत्तर: ग) 250 W
P ∝ V² for fixed R: P = 1000 × (110/220)² = 250 W.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
Twelve identical resistors, each R, form the edges of a cube. The equivalent resistance between two diagonally opposite corners (ends of a body diagonal) is:
सही उत्तर: ख) 5R/6
By symmetry the current splits 3 ways, then 6 ways, then 3 ways: R/3 + R/6 + R/3 = 5R/6.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
A copper coil has resistance 10 Ω at 0 °C. If the temperature coefficient of resistance is 0.004 K⁻¹, its resistance at 50 °C is:
सही उत्तर: क) 12 Ω
R = R₀(1 + αΔT) = 10(1 + 0.004 × 50) = 10 × 1.2 = 12 Ω.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
A point charge q is placed at one corner of a cube. The total electric flux through the cube is:
सही उत्तर: ग) q/(8ε₀)
Eight such cubes would surround the charge symmetrically, so one cube receives 1/8 of the total flux q/ε₀.
💬 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।