A radioactive nucleus emits a beta particle. Its mass number MCQ with Answer and Explanation

Explanation:
At C (centre of curvature), image is at C, real, inverted, same size. At F, image at infinity. Beyond C, between F and C, diminished. Object between F and C gives beyond C, enlarged.

Explanation:
λ = h/(mv) = 6.63×10⁻³⁴/(1×10) = 6.63×10⁻³⁵ m. Extremely small, not observable. For electron it's significant. de Broglie hypothesis: matter waves. This is modern physics.

Explanation:
Concave lens diverges light, always forms virtual, erect, diminished image on same side as object. Used in spectacles for myopia.