Test: Blow Hot, Blow Cold MCQ- 2 - Class 5 MCQ

Paper snake will move in an anti-clockwise direction when the air is cold, as cold air moves downward.

When air is blown in the cap of the pen, air molecules vibrate at a frequency corresponding to the resonance of the structure of the pen cap and correspondingly sound is produced.

• Blowing over the tea makes the tea cold.
• Blowing over rubber particles after using eraser clears the dust.
• Blowing over spectacles creates a fog-like thing on the spectacles.

Hence, the correct answer is blowing over hands after rubbing them on a snowy day.

When you fold a piece of cloth, bring it close to your mouth, and blow hard on it, you are demonstrating the concept of heat transfer. The warm air from your breath transfers heat energy to the cloth, causing it to become warm.

When you blow hard from your mouth onto your hands, the air from your mouth feels hotter than the air around. This is because the air you blow out is warmer due to the heat generated by your body.

If the woodcutter had eaten the hot potatoes without cooling them, he might have burned his mouth. It's important to cool down hot food before eating to avoid burning oneself.

• Blowing over hands on a cold day, make it warm.
• Blowing over leaves fallen on the ground makes leaves fly.
• Bowing over sharpener fillings also makes the fillings fly.
• Hence, the correct answer is blowing over the coffee makes it cold.

- Blowing air from your mouth onto spectacles adds moisture to the lenses.
- The moisture comes from the water vapor present in your breath.
- This moisture helps to loosen dirt or smudges on the lens surface.

By blowing gently and blowing hard to make different sounds, you are exploring the concept of air pressure. The force with which you blow affects the pressure of the air, resulting in various sounds.

Mini’s tea will be hotter than the air coming out of her mouth. She is cooling down the hot tea from the cooler air coming from her mouth.

When air flow upwards, paper snake spins in clockwise direction. The candle heats up the air around it and the heated air flows in the upward direction. 

The mirror becomes hazy when you blow on it because the moisture in your breath condenses on the colder surface of the mirror, creating tiny water droplets that make it appear hazy. This phenomenon occurs due to the temperature difference between your warm breath and the cooler mirror.

Sonu’s hands will be cooler than his breath. He used the warmer air coming out of his mouth to warm his cold hands.

As keeping in broad container gives the food more space and blowing over it results in blowing away the hot air coming out of food. Hence making it cold enough to consume.

Cooling down hot food like dal, roti, and rice before eating is essential to prevent burning the mouth. It helps in making the food safe to eat and enjoyable without causing any harm.