Physics
Rivers which originate from the glaciers at high altitudes have a supply of water throughout the year. This is because ice in high mountains does not melt all at once. This is due to:
- high specific heat of ice.
- low specific heat of ice.
- low specific latent heat of fusion of ice.
- high specific latent heat of fusion of ice.
Answer
high specific latent heat of fusion of ice.
Reason— Ice requires a large amount of heat energy to change from solid to liquid without a change in temperature. This is because it has a high specific latent heat of fusion—about 336 J/g. In high-altitude glaciers, even when temperatures rise slightly, the ice melts slowly and steadily over time, ensuring a continuous supply of water to rivers throughout the year.
Related Questions
A ray of light passes obliquely from an optical medium of refractive index 1.33 to another medium of refractive index 1.5. While passing from the first medium to the second, the light ray will:
- bend towards the normal.
- bend away from the normal.
- move along the normal.
- suffer total internal reflection.
You want to register your name for an examination. For registration purposes, you need a passport-size photograph of yourself. When you went to a studio, the photographer told you to sit on a chair in front of a white screen in the room.
Assertion (A) : This is purposefully done so that you as an object should stand beyond the centre of curvature of the camera lens, but surely not at an infinite distance.
Reason(R) : The characteristics of the image formed are that it can be taken on a screen and is also diminished in size.
- Both A and R are true, and R is the correct explanation of A.
- Both A and R are true, and R is not the correct explanation of A.
- A is true, but R is false.
- Both A and R are false.
What is the ratio of wavelengths between P, Q and R?
- 3:2:1
- 1:2:3
- 6:3:2
- 2:3:6