What is a transistor
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. Please obtain free notes, exams and marking guides of ... Read More
What is meant by an intrinsic material?
An intrinsic material refers to a pure semiconductor material that has not been intentionally doped with impurities. Common intrinsic semiconductors include silicon (Si) and germanium ... Read More
Explain how a p-n junction is made.
A p-n junction is created by joining p-type and n-type semiconductors together. Here's how it is made: Doping: Create p-type and n-type semiconductors by doping ... Read More
Explain why it is difficult to separate isotopes U-238 and U-235.
Their small mass difference makes physical separation processes based on mass or weight differences, less effective and more challenging. Please obtain free notes, exams and ... Read More
Describe how the radiations emitted in a cloud chamber may be identified.
A cloud chamber is a device used to visualize the paths of ionizing radiation particles. The different types of radiation can be identified based on ... Read More
What is a nuclide?
A nuclide is an atomic nucleus characterized by its number of protons and neutrons. Please obtain free notes, exams and marking guides of Physics, chemistry, ... Read More
Explain why air coming out of a valve of a ball feels cold.
This is due rapid (adiabatic) expansion accompanied with a decrease in temperature which cause a cold sensation. Please obtain free notes, exams and marking guides ... Read More
State the conditions necessary to isothermal and adiabatic reversible processes.
Isothermal process occurs at constant temperature and therefore the gas must be enclosed in thin-walled container of good thermal conductivity placed in a large het ... Read More
Explain why the intensity of solar radiation on top of earth’s atmosphere is higher than that on the earth’s surface.
Portion of the radiation is absorbed by clouds, ozone layer and other atmospheric particle before reaching earth’s surface Portion of the radiation is reflected by ... Read More
Explain why the experiment to determine the thermal conductivity of a metal, the specimen is made thin and long.
Gradient Establishment: A thin and long specimen ensures a well-defined temperature gradient along its length. This is crucial because thermal conductivity is measured based on ... Read More
Define thermal conductivity and state its units.
Thermal conductivity s the rate of heat flow per unit cross section area per unit temperature gradient Units: Wm-1K-1 Please obtain free notes, exams and ... Read More
Why does saturated vapour pressure increase with temperature
Saturated vapour pressure increases with temperature due to the increase in kinetic energy and the probability of molecules overcoming the intermolecular forces holding them in ... Read More
Derive an expression for the speed of a bicycle rider around a circular path.
Assumption v = speed of the bicycle r = radius of the circular path m= mass of the bicycle and the rider g = acceleration ... Read More
Super-heated water – meaning in physics
Superheated water is liquid water under pressure at temperatures between the usual boiling point, 100 °C (212 °F) and the critical temperature, 374 °C (705 °F). Key Characteristics: Higher Temperature: Superheated water exists at ... Read More
Explain the significance of the banked tracks.
It enables vehicles to navigate turns at higher speeds without skidding because, on banked track, a component of normal reaction supplements friction to provide the ... Read More
Describe the justification of the existence of molecules in gasses
Kinetic Molecular Theory: Particle Nature of Matter: This theory states that all matter is composed of small particles (molecules) that are in constant motion. In ... Read More
Molecular Theory Explanation of Hooke’s Law
Atomic Bonds: In a solid material, atoms are arranged in a regular pattern and are held together by interatomic forces, often visualized as tiny springs ... Read More
A stone tied to a string is whirled in a horizontal circle. Explain the motion of the stone when the string breaks.
Before the String Breaks: The stone is kept in a circular path by the tension in the string, which provides the necessary centripetal force directed ... Read More
Acceleration-meaning in physics
Acceleration is the rate of change of velocity. Find free notes, exams and marking guides from digitalteachers.co.ug website Read More
Explain the circumstances under which a person in a lit feels weightless.
When acceleration is equal to the acceleration due to gravity/when a lift experiences a free fall. i.e., the person is no longer pressing against the ... Read More
Explain why the tension in a cable of a lift when it is ascending is different from when it is descending.
The tension is greater when the lift is ascending because it has to overcome both the weight of the lift and the force due to its ... Read More