Test: Light - Year 4 MCQ

When light strikes a rough surface, it is reflected in multiple directions due to the uneven texture of the surface. This scattering of light prevents the formation of a clear reflection, making objects appear less defined.

The ray that travels from the light source to an object is called an "arriving ray." It is the initial light that illuminates the object before it is reflected back towards our eyes.

The Sun is the primary source of light in our solar system. It emits its own light and illuminates planets and moons, which then reflect that light, making them visible from Earth.

The Earth's rotation creates the illusion that the Sun moves across the sky from east to west. In reality, it is the spinning of the Earth on its axis that causes this apparent movement, affecting our daily experience of day and night.

We are able to see objects that do not generate their own light because light from a source reflects off these objects and enters our eyes. This reflection process is crucial for our visual perception of non-luminous objects.

Comets are composed of ice and dirt and have elongated orbits around the Sun. As they approach the Sun, they can develop long tails due to the sublimation of ice, which makes them visually distinctive in our solar system.

Smooth, shiny surfaces, such as mirrors, are highly effective at reflecting light, leading to clear reflections. This is due to their ability to bounce light in an organized manner, unlike rough surfaces that scatter light.

All celestial bodies, including stars (which have their own orbits), asteroids, and comets, follow defined paths around the Sun. This movement is described as their orbits, which can vary significantly in shape and duration.

Planets appear to shine in the night sky because they reflect light from the Sun. Unlike stars that generate their own light, planets are visible primarily due to the sunlight they reflect towards Earth.

The Sun is significant in the solar system because it emits light and heat, which are essential for life on Earth. It is the primary source of energy that drives weather, climate, and photosynthesis in plants.

The tilt of Earth's axis affects the seasons by changing the angle at which sunlight strikes the Earth throughout the year. This axial tilt also plays a role in the variation of daylight hours across different seasons.

A shadow appears shorter when the Sun is directly overhead because the light source is positioned almost vertically. This results in the light hitting the object at a steep angle, minimizing the shadow's length.

The Moon orbits the Earth, completing one full orbit approximately every 29 days. This relationship affects various natural phenomena, including tides and the visibility of the Moon from Earth.

A ray diagram is used to illustrate how light travels. It represents light rays as straight lines, helping to visualize the paths of light from a source to objects and how they reflect off surfaces.

The Earth takes approximately 24 hours to complete one full rotation on its axis. This rotation is responsible for the cycle of day and night that we experience regularly.

A narrow beam of light that travels from a source is referred to as a "ray." Each ray emanates from the light source and can travel in straight lines until it encounters an object, which may reflect the light.

The Earth’s rotation plays a crucial role in the formation of shadows by causing them to move and change length throughout the day. As the position of the Sun changes due to this rotation, so does the angle and length of the resulting shadows.

Rough or uneven surfaces tend to absorb light rather than reflecting it. This absorption means that such surfaces do not produce clear reflections, which can be observed in materials like wood or unpolished stone.

Mirrors have a smooth, shiny surface that allows them to reflect light effectively. This characteristic enables mirrors to create clear images of the objects in front of them, which is why they are commonly used in various applications.

Shadows are longest at sunrise and sunset because the Sun is positioned at a low angle in the sky, casting light at a shallow angle. This results in longer shadows compared to when the Sun is high in the sky.