Thermal Properties Of Matter

Step 1: Read the coordinates of points and from the – diagram: For one mole of ideal gas,
Step 2: Temperatures at and :
Step 3: Work done in the process . Since the path is a straight line,
Step 4: Change in internal energy for a monoatomic ideal gas:
Step 5: Heat supplied using the first law of thermodynamics:
Step 6: Specific heat capacity of the process:

Step 1: Newton’s law of cooling:
Step 2: For equal successive intervals, same ratio holds:
Step 3:
Step 4: But fall must be toward 26; applying exponential form gives approx 40°C. Hence → (B).

Step 1: Recall the concept of buoyant force. The buoyant force (also called upthrust) is the force exerted by a fluid on an object immersed in it. Step 2: Determine the direction of buoyant force. Buoyant force always acts vertically upward, opposite to the direction of gravitational force. Step 3: Analyze the options.

(A) Downward — incorrect
(B) Sideways — incorrect
(C) Upward — correct ✔
(D) Incorrect — a correct option exists
Step 4: Final conclusion. The buoyant force on an object due to a fluid always acts in the upward direction.