The SI unit of electric current is MCQ with Answer and Explanation

Explanation:
An electric iron contains a heating element (usually nichrome). When electric current passes through this high-resistance element, it produces heat according to Joule's law (H = I²Rt). An electric fan uses the magnetic effect (motor), a generator uses electromagnetic induction, and a transformer uses mutual induction.

Explanation:
Acceleration a = dv/dt ⇒ dv = a·dt. Integrating: ∫dv = ∫a·dt ⇒ Δv = area under a-t graph. Slope of v-t gives acceleration; area under a-t gives velocity change. Memory aid: 'a-t graph area = Δv; v-t graph area = displacement'. Graph interpretation skill essential for motion analysis in competitive exams.

Explanation:
K.E. = ½ m v² = ½ × 2 × 5² = 1 × 25 = 25 J. Use formula correctly. If velocity doubled, KE quadrupled. Unit joule.