Transformer turns ratio N_p:N_s = 1:5. If V_p = 100V, V_s is: MCQ with Answer and Explanation

Explanation:
Moderator (water, graphite) slows fast neutrons to thermal energies for efficient fission in U-235. Control rods absorb neutrons to regulate reaction. Memory tip: 'Moderator = neutron slower; Control rods = neutron absorber'. Reactor component function frequently tested in competitive nuclear physics questions.

Explanation:
In a parallel-sided glass slab, refraction at first surface bends ray towards normal; at second surface (glass to air), it bends away by equal angle, making emergent ray parallel to incident ray but shifted laterally. No net deviation, only displacement. Memory aid: 'Slab: emergent ray parallel to incident; prism: emergent ray deviated'. This ray optics concept is frequently tested in competitive exams. Always distinguish slab (parallel faces) from prism (non-parallel faces) behavior: slab causes lateral shift, prism causes angular deviation.

Explanation:
v ∝ 1/√r. If r' = 2r, v' = v/√2. Orbital velocity decreases with increasing radius. Memory aid: 'Higher orbit ⇒ slower speed; v ∝ r⁻¹/²'. Proportional reasoning question testing gravitation formula application, frequently appearing in competitive exams without heavy calculation.