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: A. is located on the emitter
Transistor schematic symbols always incorporate an explicit directional arrow directly upon the emitter. This specific arrow marker defines the correct physical path of conventional current flow. Standard electronic diag...
Answer: A. 1 N
The force exerted by a fluid stream equals the mass flow rate multiplied by velocity change. Multiplying volumetric discharge by fluid density gives the mass flow rate per second. Calculating this momentum transfer yield...
Answer: D. Non metals
Non-metals generally possess very large forbidden energy gaps between their valence and conduction bands, acting as insulators.
Answer: B. Two
A planar surface is strictly two-dimensional, possessing length and width coordinates. Any vector operating within this flat plane can be resolved along orthogonal axes. These two perpendicular axes provide a maximum lim...
Answer: C. Eight corners
A simple cubic crystal lattice features repeating structural units with specific geometric lattice point locations. Atoms, ions, or molecules in this basic lattice occupy strictly the eight geometrical corners. No additi...
Answer: C. both its mass and the angle at which it is thrown
Escape velocity depends solely on the mass and radius of the planet being escaped. Mass cancels out during the derivation equating kinetic energy to gravitational potential energy. Launch angle alters the trajectory but...
Answer: B. Electric charge
Electric charge is classified as a derived SI unit, calculated as current multiplied by time in standard measurement systems. The fundamental SI system defines base units for specific dimensions, while other composite un...
Answer: D. potential difference across galvanometer branch is zero
A Wheatstone bridge reaches balance when the galvanometer branch potential difference equals zero. No electrical current flows across the central galvanometer branch under balanced conditions. Ratio arms allow precise re...
Answer: D. 2 times
The time period of a simple pendulum is directly proportional to the square root of its length. Quadrupling the pendulum length multiplies the length value by a factor of four. Taking the square root of four yields a tim...
Answer: B. 5 cm
A complete vibrational cycle requires an object to travel outward and back twice. This motion covers a total cumulative path length equal to four times the amplitude. Dividing the total path length of twenty centimeters...
Answer: A. P1 – P2 = 1/2 ρV22
The Venturi relation is derived directly from Bernoulli equation applied to horizontal fluid flow through a pipe constriction. As fluid speed increases in a narrowed section, local static pressure drops according to ener...
Answer: D. All A, B and C are correct
A scalar multiplier can be dimensionless, have physical dimensions, or be negative when scaling a vector. Multiplying a vector by a scalar alters its magnitude and can reverse its direction if negative. Physical scaling...
Answer: A. is located on the emitter
Transistor schematic symbols use a distinct arrow to designate the semiconductor region known as the emitter. The physical placement of this directional arrow helps electronic technicians quickly identify the terminal co...
Answer: B. in adiabatic compression
Work is done directly on the enclosed gas without allowing any heat transfer. The first law of thermodynamics confirms that internal energy increases when compressive work occurs. Raising the internal energy of the gas s...
Answer: C. 1000um
Standard international metric conventions require a clear separating space between the number and unit. Writing numbers and unit symbols together without spacing violates recognized scientific formatting rules. The incor...
