Advertisements
Advertisements
प्रश्न
Explain, why no tracks are left on the ice during ice skating?
उत्तर
The weight of the body acts on a very small area of skate, in comparison to that of ice. Under this high pressure, ice melts to form water below 0°C. The water so formed makes the surface water skating more slippery. But as soon as the skater moves further, the water does not experience any pressure and re-freezes into ice leaving no track on ice surface.
APPEARS IN
संबंधित प्रश्न
What is the energy absorbed during the phase change called?
Write the approximate value of specific latent heat of ice.
- Which requires more heat: 1 g ice at 0℃ or 1 g water at 0℃ to raise its temperature to 10℃?
- Explain your answer in part (a).
A molten metal of mass 150 g is kept at its melting point 800℃. When it is allowed to freeze at the same temperature, it gives out 75,000 J of heat energy.
- What is the specific latent heat of the metal?
- If the specific heat capacity of metal is 200 J kg-1 K-1, how much additional heat energy will the metal give out in cooling to -50℃?
Explain the following temperature vs time graph.
What is meant by latent heat? How will the state of matter transform if latent heat is given off?
When a liquid is getting converted into solid, the latent heat is ………………………………
Explain the following temperature vs time graph.
What do you mean by the statement?
'The specific latent heat capacity of fusion of ice is 336 J per g'?
Explain why water is used in hot water bottles for fomentation and also as a universal coolant.
Why does weather become pleasant when it starts freezing in cold countries?
Why water get cooled in a ‘Surahi’ in hot season?
When ice is converted into water : constant temperature : : before the water evaporates : _______
How fog is formed?
Write the name.
The phase in which solid substances are converted into liquid.
Write scientific reason.
The bottom of some steel utensils used for cooking is copper.
Define specific latent heat capacity
Calculate the total amount of heat energy required to melt 200 g of ice at 0°C to water at 100°C. (Specific latent heat of ice = 336 Jg-1, specific heat capacity of water = 4.2 Jg-1 °C-1)
