NTA Abhyas JEE Main2020PhysicsThermal Properties of MatterPractice
A beaker of height H is made up of a material whose coefficient of linear thermal expansion is 3 α . It is filled up to the brim by a liquid whose coefficient of volume expansion is 3 α . If now the beaker along with its contents is uniformly heated through a small temperature T , the level of liquid will reduce by (Given, α T ≪ 1 )
Options
- Aα TH
- B3 α TH
- C9 α TH
- D6 α TH
Correct answer
B. 3 α TH
Step-by-step solution
Let A is cross - sectional area of a beaker Then, final cross - sectional area A ′ = A 1 + 6 α T Final volume of liquid V ′ = AH 1 + 3 α T Final height, H ′ = V ′ A ′ ⇒ H ′ = H 1 + 3 α T 1 + 6 α T ∼ H 1 - 3 α T Reduction in level, H - H ′ = 3 α TH