Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NTA Abhyas JEE Main2020PhysicsThermal Properties of MatterPractice

The temperature gradient in the earth's crust is 32 ° C km - 1 and the mean conductivity of earth is 0.008 cal s - 1 cm - 1 ° C - 1 . Considering the earth to be a sphere of radius 6000 km , the loss of heat by the earth every day is about

Options

  1. A10 30   cal
  2. B10 40   cal
  3. C10 20   cal
  4. D10 18 cal

Correct answer

D. 10 18 cal

Step-by-step solution

∆ Q = K A ∆ T ∆ x ∆ t = 0.008 10 2 × 4   × 22 7 6 × 10 8 2 × 32 10 3 × 86400 ≈ 10 18   cal

Practice Thermal Properties of Matter on Quantrex Academy →

More from Thermal Properties of Matter

As shown in the figure, an insulated container is fitted with a thermally conducting but immovable partition (P₁) and a freely movable but thermally insulated piston (P₂) . The par 2026The heat extracted out of x gram of water initially at 50°C to cool it down to 0°C is sufficient to evaporate (1000 - x) gram of water also initially at 50°C . The value of x (clos 2026The temperature of a metal strip having coefficient of linear expansion is increased from T₁ to T₂ resulting in increase of its length by L₁ . The temperature is further increased 2026Which of the following best represents the temperature versus heat supplied graph for water, in the range of -20^ C to 120^ C ? 202610 kg of ice at -10^ C is added to 100 kg of water to lower its temperature from 25 ^ C . Consider no heat exchange to surroundings. The decrement to the temperature of water is _ 2026A brass wire of length 2 m and radius 1 mm at 27^ C is held taut between two rigid supports. Initially it was cooled to a temperature of -43^ C creating a tension T in the wire. Th 2026Rods x and y of equal dimensions but of different materials are joined as shown in figure. Temperatures of end points A and F are maintained at 100^ C and 40^ C respectively. Given 2026An aluminium and steel rods having same lengths and cross-sections are joined to make total length of 120 cm at 30^ C . The coefficient of linear expansion of aluminium and steel a 2026 Full Thermal Properties of Matter list All NTA Abhyas JEE Main PYQs