Physics holds 894 questions with answers, free to read and with no account needed. They are grouped into 1 category: Physics.
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Answer: D. both B and C
A convex lens behaves as a diverging lens when placed in a medium with a higher refractive index than the lens material.
Answer: C. both even and odd harmonics are present
Open organ pipes have open boundaries at both ends creating displacement antinodes in standing waves. These boundary conditions permit both pressure nodes and antinodes that support a complete harmonic series. Consequent...
Answer: A. Logic gates
Logic gates are electronic circuits that perform basic Boolean logic operations to execute digital switching functions. These semiconductor-based circuits accept binary input signals of zeros and ones to produce predicta...
Answer: C. γ-rays
Gamma rays are high-frequency electromagnetic waves possessing maximum energy and exceptional penetration capabilities. Their high penetrating power allows them to pass completely through superficial skin layers to reach...
Answer: A. always an node in formed
A closed boundary in an acoustic organ pipe always forms a displacement node for standing waves. Air molecules at a closed end cannot move, resulting in zero particle velocity at the boundary. This zero motion boundary c...
Answer: C. base
An n-p-n transistor consists of a thin p-type semiconductor region sandwiched between two n-type regions. This central p-type region is specifically designed to control current flow between the emitter and collector. Con...
Answer: C. Aristotle
Aristotle authored foundational philosophical texts collectively known as Physics in antiquity. His writings attempted to explain natural terrestrial and celestial phenomena systematically. These ancient treatises domina...
Answer: D. Biology
Biology focuses specifically on living organisms and their complex life processes. Physical sciences investigate inanimate matter and the fundamental laws of the universe. Life sciences represent a completely different b...
Answer: C. a spherical wave front
A localized point light source in a uniform medium emits spherical wave-fronts. Light spreads outward uniformly in every three-dimensional direction from the source. Equal travel times from the center form expanding sphe...
Answer: C. both negative and positive charges
Liquids and gases can conduct electricity only when mobile charge carriers are present within them. Electrolytic solutions contain both positively charged metal ions and negatively charged non-metal ions moving freely. I...
Answer: C. Sphygmomanometer
A sphygmomanometer is the standard medical instrument used to measure arterial blood pressure. It uses an inflatable cuff to restrict blood flow temporarily in arteries. Pressure gauges record systolic and diastolic bloo...
Answer: D. Has magnitude -2
Vector magnitude is calculated by taking the square root of the sum of squared components. For vector A, the components squared give four plus four plus nine equaling seventeen. The true magnitude equals the square root...
Answer: D. Parabolic
A projectile hurled horizontally or at an angle follows a parabolic trajectory under uniform gravity. Constant horizontal velocity combined with uniform downward acceleration creates a symmetrical parabola. Air resistanc...
Answer: B. Decreases
Forward bias applies external voltage opposing the internal built-in electric field of a diode. This opposing voltage lowers the potential energy barrier hindering major carrier diffusion. Reduced barrier heights allow e...
Answer: B. The light emitting diode
Light-emitting diodes are specialized semiconductor diodes that emit visible light when forward-biased. Recombination of electrons and electron holes across the pn junction releases energy as photons. Different semicondu...
