JEE Main Test 8...

In a triangle, the lengths of two larger sides are 10 cm and 9 cm. If the angles of the triangle are in AP, then the length of the third side is

A steam at 100°C is passed into 1 kg of water contained in a calorimeter of water equivalent 0.2 kg at 9°C till the temperature of the calorimeter and water in it is increased to 90°C. The mass of steam condensed in kg is nearly (specific heat of water =1 cal/g°C, and latent heat of vaporisation = 540 cal/g)

An ice box made of Styrofoam (thermal conductivity = 0.01 Jm^-1 s ^-1 K^-1) is used to keep liquids cool. It has a total wall area including lid of 0.8 m 2 and wall thickness of 2.0 cm. A bottle of water is placed in the box and filled with ice. If the outside temperature is 30°C, the rate of flow of heat into the box is (in Js^-1)

Assertion (A) Water flows faster than honey.

Reason (R) The coefficient of viscosity of water is less than honey.

Two rigid boxes containing different ideal gases are placed on a table. Box A contains one mole of nitrogen at temperature T₀, while box B contains one mole of helium at temperature (7/3)T₀ . The boxes are then put into thermal contact with each other and heat flows between them until the gases reach a common final temperature (Ignore the heat capacity of boxes). Then, the final temperature of the gases, T_f, in terms of T₀ is

The coefficient of χ³ in the infinite series expansion of 2/(1– χ) (2 – χ), for |χ| < 1 is

The efficiency of a Carnot engine working between 800 K and 500 K is