Many fish thrive in Antarctic water, where the temperature is always below zero. How do they manage to keep their body fluids uneffected from freezing ?

A : Antarctic fishes have blubber to withstand sub zero temperatures. R: Blubber are proteins which allow the freezing of body fluids.

An ice cube whose mass is 50 g is taken from a refrigerator where its temperature was -10^@C . If no heat is gained or lost from outside, how much water will freeze onto the cube if it is dropped into a beaker containing water at 0^@C ? Latent heat of fusion =80 kcal//kg , specific heat capacity of ice =500 cal//kg//K .

If a body moves through a liquid or a gas then the fluid applies a force on the body which is called drag force. Direction of the drag force is always opposite to the motion of the body relative to the fluid. At low speeds of the body, drag frog ( F _(P)) is directly proportional to the speed. F_(D) = kv What K is a proportionally constant and it depends upon the dimension of the body moving in air at relatively high speeds, the drag force applied by air an the body is proportional to v^(2) Where this proportionally constant K can be given by K_(2) rho CA Where rho is the density of air C is another constant givig the drag property of air A is area of cross-section of the body Consider a case an object of mass m is released from a height h and it falls under gravity. As it's speed increases the drag force starts increasing on the object. Due to this at some instant, the object attains equilibrium. The speed attained by the body at this instant is called "terminal speed" of the body. Assume that the drag force applied by air on the body follows the relation F_(D) = kv ,neglect the force by buoyancy applied by air on the body then answer the following questions. What is the pattern of acceleration change of the body ?

If a body moves through a liquid or a gas then the fluid applies a force on the body which is called drag force. Direction of the drag force is always opposite to the motion of the body relative to the fluid. At low speeds of the body, drag frog ( F _(P)) is directly proportional to the speed. F_(D) = kv What K is a proportionally constant and it depends upon the dimension of the body moving in air at relatively high speeds, the drag force applied by air an the body is proportional to v^(2) Where this proportionally constant K can be given by K_(2) rho CA Where rho is the density of air C is another constant givig the drag property of air A is area of cross-section of the body Consider a case an object of mass m is released from a height h and it falls under gravity. As it's speed increases the drag force starts increasing on the object. Due to this at some instant, the object attains equilibrium. The speed attained by the body at this instant is called "terminal speed" of the body. Assume that the drag force applied by air on the body follows the relation F_(D) = kv ,neglect the force by buoyancy applied by air on the body then answer the following questions. What is the terminal speed of the object ?

A fish in a lake (refractive index 4//3 for water ) is viewed through a convex lens. From water surface, the lens is placed in air at half of the distance of the fish from the water surface, so that the image is formed at the fish itself. The focal length of the lens is how many times the depth of fish in water?

Most substances contract on freezing . However, water does not belong to this category. We know that water expands on freezing. Further , coefficient of volume expansion of water in the temperature range from 0^(@)C to 4^(@)C is negative and above 4^(@)C it is positive . This behaviour of water shapes the freezing of lakes as the atmospheric temperature goes down and it is still above 4^(@)C . As the atmospheric temperature goes below 4^(@)C

Most substances contract on freezing . However, water does not belong to this category. We know that water expands on freezing. Further , coefficient of volume expansion of water in the temperature range from 0^(@)C to 4^(@)C is negative and above 4^(@)C it is positive . This behaviour of water shapes the freezing of lakes as the atmospheric temperature goes down and it is still above 4^(@)C . As the atmospheric temperature goes below 4^(@)C

Most substances contract on freezing . However, water does not belong to this category. We know that water expands on freezing. Further , coefficient of volume expansion of water in the temperature range from 0^(@)C to 4^(@)C is negative and above 4^(@)C it is positive . This behaviour of water shapes the freezing of lakes as the atmospheric temperature goes down and it is still above 4^(@)C . If the atmospheric temperature is below 0^(@)C and ice begins to form at t = 0 , thickness of ice sheet formed up to a time 't' will be directly proprotional to

Most substances contract on freezing . However, water does not belong to this category. We know that water expands on freezing. Further , coefficient of volume expansion of water in the temperature range from 0^(@)C to 4^(@)C is negative and above 4^(@)C it is positive . This behaviour of water shapes the freezing of lakes as the atmospheric temperature goes down and it is still above 4^(@)C . If the atmospheric temperature is below 0^(@)C

How many statements/s are true ? A. Temperature is the most relevant ecologically environmental factor. It ranges from subzero levels in polar areas and high altitudes to gt50^@C in tropical deserts in summer. B. A few organisms can tolerate and thrive in a wide range of temperature they are called eurythermal. C. The productivity and distribution of plants are also heavily dependent on water . D. In the aquatic environment , the sediment characteristics often determine the type of benthic animals that can thrive there.