Light is not visible underwater because water absorbs and scatters light. As light travels through water, it is absorbed by the water molecules and particles, causing it to lose intensity and become less visible. Additionally, the scattering of light by suspended particles and molecules in the water further reduces its visibility. This is why as you go deeper underwater, the amount of visible light decreases, eventually leading to complete darkness in the deep ocean. **

One way to make electric fields visible is by using a device called an electroscope, which can detect the presence of electric charges. Another method is to use a tool called a field mill, which can measure the strength and direction of electric fields. Additionally, electric fields can be visualized using techniques such as using charged particles to trace out the field lines or by using special materials that change color in the presence of an electric field. **

Electric fields can be made visible using a device called an electroscope, which consists of a metal rod with a ball on top and two thin metal leaves attached to the bottom. When an electric field is applied to the electroscope, the metal leaves will either repel or attract each other, indicating the presence and direction of the electric field. Another way to visualize electric fields is by using a device called a cathode ray tube, which can show the path of charged particles in an electric field. Additionally, electric fields can also be visualized using a technique called electric field mapping, where the field strength and direction are represented by lines or vectors on a diagram. **

Visible light is easily shielded because it is made up of electromagnetic waves that can be absorbed, reflected, or refracted by various materials. For example, opaque materials such as wood, metal, and plastic can absorb and block visible light, while reflective surfaces like mirrors can bounce light away. Additionally, transparent materials like glass and water can refract and scatter light, making it difficult for it to pass through. These properties make visible light easily shielded by a wide range of materials, making it possible to control and manipulate the passage of light in various applications. **

One can make a light beam visible by introducing particles or dust into the air that can scatter the light, creating a visible path for the beam. Another method is to shine the light beam through a medium that can reflect or refract the light, such as a prism or a mirror. Additionally, using a fog machine or smoke can help make the light beam more visible by creating a contrast between the beam and the surrounding environment. **

No, eyeglass scratches are not only visible in extreme light. While scratches may be more noticeable in bright light due to the reflection and refraction of light off the surface of the lens, they can still be seen in normal lighting conditions. Scratches can affect the clarity of vision and cause glare, regardless of the lighting environment. It's important to take care of your eyeglasses to prevent scratches and maintain clear vision. **

No, glasses scratches are not only visible in extreme light. Scratches on glasses can be visible in various lighting conditions, depending on the severity of the scratch. Even in normal or dim lighting, scratches can be noticeable and may affect the clarity of vision through the glasses. It is important to take care of glasses to prevent scratches and maintain their quality. **

Light rays are not visible in space because there is no atmosphere to scatter the light. In the absence of an atmosphere, there are no particles to reflect or scatter the light, making it appear as though there are no light rays. Additionally, the vacuum of space does not contain any medium for the light to interact with, further contributing to the lack of visible light rays. **