Physics holds 894 questions with answers, free to read and with no account needed. They are grouped into 1 category: Physics.
Attempt each question before revealing the answer, and keep a note of the ones you get wrong — those are the topics worth reading about properly. If an answer looks wrong, there is a link to report it on every question.
Answer: B. ΔL/LΔT
The linear thermal expansion coefficient is defined as fractional length change per degree temperature change. Mathematically this ratio is expressed as alpha equal to delta L divided by the product of L and delta T. Div...
Answer: D. Bulb
Incandescent light bulbs produce light through thermal resistance heating filaments. Electric current flows through a tungsten wire until it glows white hot. This resistive process does not involve tuned frequency resona...
Answer: C. 2 volt
Potential difference across terminals is calculated by multiplying current by resistance according to Ohm's law. Multiplying the current by the galvanometer resistance yields a potential difference of two volts. Circuit...
Answer: A. he/ev
Accelerated electrons convert kinetic energy into maximum X-ray photon energy. Equating eV to hc over lambda yields the minimum X-ray wavelength. Rearranging this equation gives lambda equal to hc divided by eV. X-ray tu...
Answer: A. Mass
The equation of continuity in fluid dynamics expresses the conservation of mass for a flowing fluid. This principle dictates that the mass flow rate entering a pipe must equal the mass flow rate exiting at any other poin...
Answer: D. its momentum is doubled
Linear momentum equals mass multiplied by velocity, giving a directly proportional relationship. Doubling the movement speed while keeping mass constant doubles the total momentum. Momentum is a vector quantity directed...
Answer: C. 6.00 s
Kinematic equations for vertical projectile motion calculate a total flight time of six seconds. The stone travels upward, peaks, and falls past the cliff before hitting the ground. Solving the quadratic displacement equ...
Answer: D. different with refractive index of core higher than cladding
Total internal reflection confines light rays within the core of an optical fiber cable. This guiding mechanism requires the central core material to possess a higher refractive index than cladding. Light striking the co...
Answer: B. Streamline
An idealized fluid is modeled as completely non-viscous and incompressible in physics. At low flow velocities, fluid particles move along smooth, non-intersecting trajectories. This orderly fluid motion is formally class...
Answer: A. Time
Derived physical quantities are defined mathematically as combinations of fundamental base physical quantities. Time is recognized internationally as an independent base physical unit rather than a combination of other d...
Answer: B. Shunt
A shunt is a low-resistance conductor connected in parallel to divert excess current away from a device. By offering an alternate path of minimal resistance, it protects sensitive meter movements from damage. Shunt resis...
Answer: B. massive nucleus splits to form smaller fragments
Nuclear fission is a process where a heavy, massive atomic nucleus splits into smaller lighter fragments. This splitting event is triggered by neutron absorption in fissile isotopes like uranium. The reaction releases su...
Answer: C. ÀKe2/rn
The electrostatic potential energy of an electron in an orbit at distance r from a positive core is negative, given by -Ke^2/r.
Answer: C. 3N & 6N
The magnitude of the vector resultant must fall within the range of the difference and sum of the two vectors. For two vectors of three newtons and six newtons, the minimum possible resultant is three newtons. The maximu...
Answer: C. Equal to the weight of the stone
At the highest point of a vertical loop, tension plus weight equals centripetal force, making tension less than at the bottom.
