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: C. point
A point in geometry is defined as a zero-dimensional object that has a precise location in space but no length, width, or height. Points serve as the foundational building blocks for constructing lines, planes, and compl...
Answer: C. mass
Inertia represents the natural resistance of any physical object to changes in velocity. Mass quantifies how much matter an object contains and resists acceleration. Objects with greater mass exhibit proportionally great...
Answer: C. Stephens law
Stefan's law states that total thermal radiation emitted is proportional to the fourth power of temperature. Doubling the absolute temperature increases the radiated thermal energy by a factor of sixteen. Stefan-Boltzman...
Answer: C. aluminium
Aluminum is a trivalent element that introduces electron deficiencies into semiconductor crystal lattices. These deficiencies create electron holes, classifying aluminum as an acceptor rather than a donor. Donor impuriti...
Answer: B. material objects and electromagnetic radiation only
General relativity describes gravity as the curvature of spacetime caused by mass-energy distribution. Electromagnetic radiation possesses energy and momentum, contributing to the total stress-energy tensor in spacetime....
Answer: C. Both 1st and 3rd
Both rectangular vector components share positive signs in the first quadrant. Third quadrant coordinates yield negative signs for both horizontal and vertical components. Matching algebraic signs occur exclusively in th...
Answer: C. infinite
Relativistic mass approaches infinity as an object with mass attempts to reach the speed of light. The denominator in the relativistic mass equation approaches zero as velocity approaches the speed of light. Dividing res...
Answer: D. AC transformer and DC generator
AC transformers operate entirely through electromagnetic induction without any moving mechanical parts. Traditional electromechanical instruments rely on physical moving coils and mechanical pointers to display readings....
Answer: B. A unit vector
A unit vector is defined as a vector that has a magnitude or length of exactly one, often used to indicate direction. Dividing any non-zero vector by its own magnitude creates a corresponding unit vector. Unit vectors ar...
Answer: C. adiabatic
No heat enters or leaves the thermodynamic system during an ideal adiabatic expansion process. Entropy change is defined mathematically as the ratio of reversible heat transfer to absolute temperature. Since the heat tra...
Answer: C. 10-3 sec
Atomic lasers rely on long lived metastable excited states to achieve population inversion successfully. These specific metastable energy states typically exhibit lifetimes on the order of ten to the minus three seconds....
Answer: C. 300 watt
Electrical resistance is inversely proportional to electrical power when operating at a constant standard voltage level. Using the formula resistance equals voltage squared divided by power yields a smaller value for hig...
Answer: B. coloured fringes will be seen
White light contains a continuous spectrum of different visible wavelengths travelling together simultaneously. Each individual wavelength forms its own distinct interference fringe pattern offset slightly by color. Supe...
Answer: C. Jupiter
Jupiter possesses the largest mass and radius among all planets in our solar system. Escape velocity increases directly with the mass of the planetary body and its gravitational field strength. The enormous gravitational...
Answer: C. S=Vt2
Dimensional verification requires both sides of an equation to match dimensions. Equation C equates length on the left to length multiplied by time squared. Because time squared remains unmatched, this physical equation...
