"Cathetal prisms readily yield the phenomena of total reflection as shown, and are often used when light…

A volume of a truncated right triangular prism is equal to the product of its base by one third the…

A volume of a truncated right triangular prism is equal to the product of its base by one third the…

Illustration used to prove "Two angles whose sides are perpendicular each to each are either equal or…

"The quartz crystals are said to be right or left handed, depending upon whether these faces are to…

"If used, the Directional Arrow auxiliary sign shall be mounted below the route sign in directional…

"If used, the Directional Arrow auxiliary sign shall be mounted below the route sign in directional…

"If used, the Directional Arrow auxiliary sign shall be mounted below the route sign in directional…

This directional arrow is used to indicate that something is located to the right.

This directional arrow is used to indicate that something is located to the right.

This directional arrow is used to indicate that something is located to the right.

This directional arrow is used to indicate that something is located to the right.

"Right hand rule to determine the direction of magnetic field around a conductor carrying a current.…

"Right hand palm rule to determine the direction of the magnetic field around a conductor carrying a…

"A rule for direction of induced current which in some cases, is more conveniently applied than Fleming's…

"Fleming's rule for direction of induced current. Extend the thumb, forefinger and middle finger of…

"The palm rule for direction of induced current: If the palm of the right hand be held against the direction…

"Right hand rule for polarity of a solenoid: If the solenoid be grasped in the right hand, so that the…

"Without changing the grasp of the right hand, place the piece on the right shoulder, barrel up and…

"In any right triangle, the square described on the hypotenuse is equal to the sum of the squares described…

"If used, the Directional Arrow auxiliary sign shall be mounted below the route sign in directional…

"If used, the Directional Arrow auxiliary sign shall be mounted below the route sign in directional…

"If used, the Directional Arrow auxiliary sign shall be mounted below the route sign in directional…

"Science has succeeded in classifying the thousands of known crystals in six systems, to each of which…

"Science has succeeded in classifying the thousands of known crystals in six systems, to each of which…

In Western cultures a death mask is a wax or plaster cast made of a person's face following death. Death…

In Western cultures a death mask is a wax or plaster cast made of a person's face following death. Death…

"Raise the arm laterally until horizontal; carry it to a vertical position above the head and swing…

Illustration of a leaning tower with a perpendicular drawn from the top of the tower to the ground to…

Illustration of a palm tree that is perpendicular to the ground. The tree is perfectly straight, as…

Oblique triangle with perpendicular drawn and angle of measure 35 ° 38" given, and sides of 88'…

Oblique triangle with perpendicular drawn to form two right triangles, one with angle measuring 36 °…

Illustration of a right triangle with the midpoint of the hypotenuse drawn.

Illustration of a right triangle with one angle the double of the other.

Illustration showing two equal right triangles. This can be used to show that two right triangles are…

"Direction of the needle when placed at a right angle to the uniting wire." -Comstock 1850