What is the equivalent capacitance when three capacitors of 3 microfarads each are connected in series? MCQ with Answer and Explanation

Explanation:
Convex mirror diverges light, forms virtual, erect, diminished image behind mirror for any object position. Focal length positive by sign convention but image always virtual (upright). Used in rear-view mirrors.

Explanation:
Transformer changes AC voltage.

Explanation:
For low Earth orbit (r ≈ R_earth), orbital period T = 2π√(r³/GM). Using g = GM/R², T = 2π√(R/g). With R = 6.4×10⁶ m, g = 9.8 m/s², T ≈ 2×3.14×√(6.4e6/9.8) ≈ 6.28×√(653061) ≈ 6.28×808 ≈ 5076 s ≈ 84.6 minutes. Memory aid: 'Low orbit period ≈ 84 min; geostationary = 24 hours'. This standard result is frequently tested in competitive exams. Always recall that period increases with orbital radius; competitive exams often compare low orbit vs geostationary periods.