The buoyant force on an object immersed in a fluid depends on
A. Density of the fluid and volume of displaced fluid
B. Shape of the container
C. Density of the object
D. Depth of immersion
Answer: Option A
Solution (By JKSSB Mock Tests)
Buoyant force = weight of displaced fluid = ρ_fluid × V_displaced × g. Independent of depth (if fluid incompressible) and object's density, though object density determines if it floats. Shape affects volume displaced when floating.
Explanation:
Thomas Alva Edison invented the practical incandescent light bulb in 1879. He also invented phonograph. Tesla contributed to AC system. Faraday electromagnetic induction. Bell telephone.
Explanation:
RMS value of AC is defined such that I_rms²R = average power dissipated, same as DC current I_dc would produce (I_dc²R). Thus I_rms = I₀/√2 for sinusoidal AC. This definition ensures power calculations use RMS values. Memory tip: 'RMS: heating effect equivalent to DC; I_rms = 0.707 I₀ for sine wave'. This AC fundamentals concept is frequently tested in competitive exams. Always use RMS values for power calculations in AC circuits; peak values overestimate power.
Explanation:
Sound requires material medium for mechanical wave propagation. Vacuum lacks particles to transmit vibrations. Light (EM wave) travels through vacuum. Memory tip: 'Sound = mechanical wave ⇒ needs medium; light = EM wave ⇒ no medium needed'. Fundamental wave property frequently tested in competitive exams to assess medium-dependence understanding.
No comments yet. Be the first to start the discussion!