حرارتی طبیعیات

What is the maximum efficiency of an engine working between 600 K and 300 K?

• 1 25%
• 2 75%
• 3 50%
• 4 100%

The power radiated by a hot body is proportional to its absolute temperature raised to the power of:

• 1 1
• 2 2
• 3 3
• 4 4

A sealed rigid container of gas is heated from 27 degrees C to 327 degrees C. By what factor does the pressure change?

• 1 It doubles
• 2 It halves
• 3 It becomes 12 times larger
• 4 It does not change

A gas expands at a constant pressure of 1 x 10^5 Pa, and its volume increases by 2 x 10^-3 m3. How much work does it do?

• 1 50 J
• 2 100 J
• 3 200 J
• 4 2000 J

A 1 m metal rod lengthens by 1.2 mm when its temperature rises by 100 degrees C. What is its coefficient of linear expansion?

• 1 1.2 x 10^-5 per degree C
• 2 1.2 x 10^-3 per degree C
• 3 1.2 x 10^-2 per degree C
• 4 1.2 x 10^-7 per degree C