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
There are many different processes and phenomena that emit electromagnetic radiation. Humans have taken advantage of many of these processes to develop technologies that use electromagnetic radiation.
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
The beauty of a coral reef, the warm radiance of sunshine, the sting of sunburn, the X-ray revealing a broken bone, even microwave popcorn—all are brought to us by electromagnetic waves. The list of the various types of electromagnetic waves, ranging from radio transmission waves to nuclear gamma-ray (γ-ray) emissions, is interesting in itself.
Even more intriguing is that all of these different phenomena are manifestations of the same thing—electromagnetic waves (see Figure 15.1). What are electromagnetic waves? How are they created, and how do they travel? How can we understand their widely varying properties? What is the relationship between electric and magnetic effects? These and other questions will be explored.
Photoelectric materials emit electrons when they absorb light of a high-enough frequency.
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.