Thermodynamics

An engine with an efficiency of 0.19 does 998 J of work.

How much energy is taken in by heat?

eff = W_net ÷ Q_h

• 5.3 x 10⁴ Pa

• 5.3 x 10³ J

• 1.89 x 10² J

• 1.89 x 10³ J

An engine with an efficiency of 0.29 takes in 693 J as

heat. How much work does the engine do?

eff = W_net ÷ Q_h

• 3.23 10³ J

• 1.67 x 10² J

• 2.39 x 10³ J

• 2.0 x 10² J

Find the efficiency of an engine that receives 571 J as

heat and loses 463 J as heat per cycle.

eff = Q_c ÷ Q_h − 1

• 189

• 0.189

• .233

• .81

A steam engine absorbs 1.98 × 105 J and expels 1.49 × 105 J in each cycle.

Assume that all of the remaining energy is used to do work.

What is the engine’s efficiency?

eff = Q_c ÷ Q_h − 1

• 0.247

• 0.33

• 0.752

• 0.43

A steam engine absorbs 1.98 × 105 J with an efficiency of .247

Assume that all of the remaining energy is used to do work.

How much work is done in each cycle?

eff = W_net ÷ Q_h

• .49x 10⁴ J

• 3.3 x 10⁴ J

• 4.9 x 10⁴ J

• 5.3 x 10⁴ J