The graph between velocity and time for uniform acceleration is MCQ with Answer and Explanation

Explanation:
The SI prefix 'femto' denotes a factor of 10⁻¹⁵. This is standardized by the International Bureau of Weights and Measures. Common prefixes: pico (10⁻¹²), femto (10⁻¹⁵), atto (10⁻¹⁸), nano (10⁻⁹). Femtometer (10⁻¹⁵ m) is used in nuclear physics to measure atomic nuclei sizes. Exam tip: Remember the sequence: pico, femto, atto for decreasing scales. This question tests fundamental knowledge of SI prefixes essential for unit conversions in competitive examinations.

Explanation:
Kinetic energy (K) and momentum (p) are related by K = p^2 / 2m. If momentum increases by 50%, the new momentum p' = p + 0.5p = 1.5p. The new kinetic energy K' = (1.5p)^2 / 2m = 2.25 (p^2 / 2m) = 2.25 K. This means K has increased by 1.25 K, which is a 125% increase. Understanding quadratic relationships is crucial for such problems.

Explanation:
Ionosphere contains ions and free electrons, reflects radio waves back to Earth, enabling long-distance radio communication. Used in skywave propagation. Troposphere weather layer.