Question
What is a shadow? How is it formed? How does the colour of an opaque object affect the colour of the shadow?
✓
Answer
A shadow is a dark outline or image cast by an opaque object that blocks light coming from a source of light. It is formed when light hits the opaque object which does not let the light pass through. Everywhere else around the opaque object, the light continues in a straight path until it bounces off the ground or wall behind the object. The wall or ground behind the opaque object is the screen. On this screen is a dark patch, or shadow, with the same outline as the object surrounded by light. The colour of the opaque object does not affect the colour of the shadow that is formed.
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Collect samples of some solid substances such as sugar, salt, chalk powder, sand and ; sawdust. Take five glasses or beakers. Fill each one of them about two-thirds with water. Add a small amount (spoonful) of sugar to the first glass, salt to the second and similarly, add small amounts of the other susbtances into the other glasses. Stir the contents of each of them with a spoon. Wait for a few minutes. Observe what happens to the substances added to water. Note your observations as shown in Table.
Collect samples of some solid substances such as sugar, salt, chalk powder, sand and ; sawdust. Take five glasses or beakers. Fill each one of them about two-thirds with water. Add a small amount (spoonful) of sugar to the first glass, salt to the second and similarly, add small amounts of the other susbtances into the other glasses. Stir the contents of each of them with a spoon. Wait for a few minutes. Observe what happens to the substances added to water. Note your observations as shown in Table.
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