A capacitor of capacitance C is charged to voltage V. The energy stored is:
A. CV²
B. CV
C. ½CV²
D. ½C/V
Answer: Option C
Solution (By JKExamLibrary)
Energy stored in capacitor U = ½CV² = ½QV = Q²/(2C). This derives from work done to charge the capacitor against increasing voltage. Option A has wrong dimensions (energy should be joules, CV is coulomb-volt = joule, but missing factor ½); C and D are dimensionally incorrect. Memory tip: 'Capacitor energy = ½CV², analogous to spring energy ½kx²'. This formula-based question tests electrostatics knowledge, frequently appearing in competitive exams. Always recall the three equivalent forms and choose based on given quantities.
Explanation:
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Explanation:
At highest point velocity is zero, but acceleration due to gravity is still g (9.8 m/s²) downward. This causes it to fall back. Acceleration constant throughout free fall.
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