Construction of a Circle: 3 Videos
Video 1: Construction of a circle when its radius is known
Video 2: Examples of how to construct a circle
Video 3: Common mistakes made when constructing a circle
Video 1: Construction of a circle when its radius is known
Video 2: Examples of how to construct a circle
Video 3: Common mistakes made when constructing a circle
Video 1: How to construct a line segment
Video 2: Examples of constructing different line segments
Video 3: Common mistakes made when constructing a line segment
Video 1: What are perpendiculars and perpendicular bisectors and how to construct them
Video 2: How to draw a perpendicular and perpendicular bisector using a ruler and a compass
Video 3: Examples related to the construction of perpendiculars and perpendicular bisectors on a line segment
Video 4: Common mistakes made when constructing perpendiculars and perpendicular bisectors
The idea of the electric field, how it's useful, and explains how the electric field is defined.
Video 1: How to construct a copy of an angle
Video 2:
Video 3: Common mistakes made when constructing an angle as a copy of another
Video 1: How to construct angles of a given measurement using paper and a protractor
Video 2: How to construct angles of a given measurement using a compass
Video 3: Examples of constructing angles of specific measurements
Video 4: Common mistakes made when constructing angles of specific measurements
Forces at a distance are explained by fields (gravitational, electric, and magnetic) permeating space that can transfer energy through space. Magnets or electric currents cause magnetic fields; electric charges or changing magnetic fields cause electric fields.
Magnetism is an interaction that allows certain kinds of objects, which are called ‘magnetic’ objects, to exert forces on each other without physically touching. A magnetic object is surrounded by a magnetic ‘field’ that gets weaker as one moves further away from the object. A second object can feel a magnetic force from the first object because it feels the magnetic field of the first object. The further away the objects are the weaker the magnetic force will be.
Electric charge comes in two varieties, which we call positive and negative. Like charges repel each other, and unlike charges attract each other. Thus, two positive charges repel each other, as do two negative charges. A positive charge and a negative charge attract each other.
How do we know there are two types of electric charge? When various materials are rubbed together in controlled ways, certain combinations of materials always result in a net charge of one type on one material and a net charge of the opposite type on the other material. By convention, we call one type of charge positive and the other type negative.