Page 127 - Physics - XI

Case Study-based Questions

Read the paragraph and answer the questions that follow.
10 J heat is supplied to a metal body of mass 800 g at atmospheric pressure. The initial temperature of
5
the body is 20°C, specifi c heat of metal = 300 J kg °C , relative density of metal = 8.0, coeffi cient of
–1
–1
volume expansion of metal = 6 × 10 °C , and atmospheric pressure, P = 10 Pa. Finally, the temperature
–1
5
–5
s
of the body becomes T. During this, the heat energy supplied is equal to the product of mass, specifi c
heat, and change in temperature.
Q1. The value of T is
a. 438.66°C b. 55.55°C c. 61.15°C d. 436.66°C

Q2. Increase in volume in cm is
3
a. 0.50 b. 2.50 c. 5.00 d. 0.25

Q3. Find the work done by the body on the surrounding.
a. 0.25 J b. 2.5 J c. 0.50 J d. 0.75 J

Q4. Change in internal energy is

a. 99.75 J b. 999.75 J c. 9999.75 J d. 99999.75 J
Answer key

1. (d), 2. (b), 3. (a), 4. (d)

Assertion-Reason Type Questions

These consist of two statements– Assertion (A) and Reason (R). Answer these questions by selecting
the appropriate option given below:
a. Both A and R are true and R is the correct explanation of A.

b. Both A and R are true and R is not the correct explanation of A.
c. A is true but R is false.

d. A is false but R is true.
1. Assertion(A) : If water is kept in an open container at 4°C, it overfl ows when heated or cooled.

Reason(R) : Volume of water expands below and above 4°C.
2. Assertion(A) : Fahrenheit is the smallest unit of measuring temperature.
Reason(R) : Fahrenheit was the fi rst temperature scale used for measuring temperature.

3. Assertion(A) : Specifi c heat capacity is the cause of formation of land and sea breeze.

Reason(R) : The specifi c heat of water is more than land.
4. Assertion(A) : A tumbler of thick glass bottom gets cracked when hot liquid is poured into it.
Reason(R) : Outer surface of the tumbler expands suddenly.
Answer key

1. (a), 2. (c), 3. (a), 4. (c)

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