Hypocycloid
A hypocycloid is a special plane curve generated by the trace of a fixed point on a small circle that rolls within a larger circle. If the radius of a large circle is \(R\), and the … more
Classroom Resources
Hypocycloid drawing tool
This is a tool that draws a hypocycloid figure made on a 3D printer. For a description of the hypocycloid, see here(link). 3D print data The gear ratios are 24 for the external gear and 17, … more
Free Fall Motion Analysis
Why do light and heavy objects fall at the same time? The change in speed due to gravity is the same for all objects because the force and inertia acting on an object are proportional to … more
Mechanical Energy Conversion 2
Mechanical energy As the roller coaster descends from a high place, the height decreases, and the speed increases, so the potential energy decreases, and the kinetic energy increases. Therefore, potential energy is converted into kinetic energy … more
Hypocycloid 2
A hypocycloid is a special plane curve generated by the trace of a fixed point on a small circle that rolls within a larger circle. If the radius of a large circle is R, and the … more
“Free falling” or “Thrown to the horizontal direction”
How to use the simulation Drag the ball with your mouse to free fall it in the air. Drag your mouse on the cliff to observe the parabolic motion. You can change the horizontal speed by … more
Earth’s Revolution and Seasons (WebGL)
Earth Rotation and Seasonal Changes The Earth’s rotation axis is tilted at an angle of about 23.5 ° to the orbital axis. Because of this inclination, seasonal changes occur like spring, summer, autumn, and winter. The … more
AC Power Generator
Electromagnetic induction Moving a magnet around a coil changes the magnetic field inside the coil, which causes current to flow through the coil. This phenomenon is called ‘electromagnetic induction’; the current flowing through the coil is … more
Home Wiring (Indoor Wiring)
Build the indoor wiring to make the electric appliance work. Home wiring All electrical devices have a resistance value, and this resistor limits electric current. A power strip or indoor wiring is a parallel connection of … more
Faraday’s Law of Electromagnetic Induction
Electromagnetic induction Moving the magnet around the inductor will change the inductor’s magnetic field, which will cause the current to flow through the inductor. This phenomenon is called electromagnetic induction. The current flowing in the inductor … more
PCR (Polymerase Chain Reaction)
Find the task sequence to amplify DNA. PCR (Polymerase Chain Reaction) PCR is a method for repeatedly amplifying a specific gene sequence from a small DNA sample. PCR goes through three basic steps. DNA denaturation Heat … more
Continental Drift (Continental Drift Theory)
Move the continents to create a connected supercontinent (Pangea).