Nutrition in Plants — Science STD 7 — Question

One winter morning, Priya made a cup of hot tea and placed the metal spoon inside it. She held the cup in her hands to feel warm. After a few minutes, she noticed the metal spoon had become hot. Then, she placed the cup on the table near the window where sunlight was coming in. She felt warm standing in the sunlight even without touching anything. Later, she saw the steam rising from the tea and disappearing into the air.
1. Why did the metal spoon become hot?
2. How did Priya feel warm just by standing in the sunlight?
3. What is the process called when hot steam rises from the tea?

Blue litmus paper is dipped in a solution. It remains blue. What is the nature of the solution? Explain.

The side mirror of a scooter got broken. The mechanic replaced it with a plane mirror. Mention any inconvenience that the driver of the scooter will face while using it?

What unusual qualities of wool make it a very useful fibre?

If someone is suffering from the problem of acidity after over eating, which of the following would you suggest as remedy?
Lemon juice, vinegar, baking soda solution.
Give reason for your choice.

State the factors on which amount of heat produced depends?

Define deforestation. Write the factors responsible for it.

What is sludge? Explain how it is treated.