The blue spark seen when turning up an electric stove is caused by the ignition of the gas that is released when the stove is turned on. When the stove knob is turned, it releases a small amount of gas into the burner, and when the electric spark ignites the gas, it creates a blue flame. This blue flame indicates that the gas is burning cleanly and efficiently. **

The router is turning slightly yellow due to heat because the heat is causing the plastic casing of the router to discolor. When electronic devices like routers generate heat during operation, it can cause the plastic casing to change color, typically turning yellow or brown. This discoloration is a common occurrence with electronic devices that generate heat and is usually a cosmetic issue that does not affect the functionality of the router. **

Longitudinal turning involves cutting along the length of the workpiece, while face turning involves cutting across the face of the workpiece. Longitudinal turning is used to create cylindrical shapes and grooves, while face turning is used to create flat surfaces and contours. Additionally, longitudinal turning is typically used for creating external features, while face turning is used for creating internal features. **

Turning off refers to the action of deactivating or shutting down a device, system, or appliance. This typically involves stopping the flow of power or energy to the device, causing it to cease functioning. On the other hand, turning on refers to the action of activating or starting a device, system, or appliance. This involves initiating the flow of power or energy to the device, allowing it to begin functioning. In essence, turning off stops the operation of something, while turning on initiates its operation. **

Face turning and longitudinal turning are two different types of machining operations used in metalworking. Face turning involves cutting material from the surface of a workpiece to create a flat surface, while longitudinal turning involves cutting material from the length of the workpiece to create a cylindrical shape. In face turning, the cutting tool moves perpendicular to the workpiece, while in longitudinal turning, the cutting tool moves parallel to the workpiece. Overall, the main difference between the two is the direction in which the cutting tool moves in relation to the workpiece. **

A turning point with a horizontal turning tangent occurs when the slope of the curve at that point is zero, meaning the tangent line is horizontal. This indicates that the function changes from increasing to decreasing or vice versa at that point. In other words, the function reaches a maximum or minimum value at that point. This type of turning point is also known as a stationary point. **

No, once you turn off your electric stove, the heating elements will begin to cool down and the stove will not continue to heat up. The heat generated by the elements will gradually dissipate, and the stove will return to room temperature. However, it's important to remember that the stove surface may remain hot for a short period after being turned off, so caution should be exercised to avoid burns. **

There could be several reasons why it's not turning. It could be a mechanical issue such as a broken or worn-out part, a lack of lubrication, or a problem with the power source. It could also be an electrical issue such as a faulty motor or a problem with the wiring. It's important to troubleshoot and diagnose the specific problem in order to determine the best course of action to fix it. **