Question

A heat engine getting energy from gasoline takes in 10,000 J of heat and converts 2000 J into work. The heat of combustion (transformation) is Lc = 5.0 × 10⁴ J/g. (a) What is the efficiency of the heat engine? (b) During each cycle how much heat will be released by the engine in the heat sink? (c) How much gasoline is burnt in each cycle? (d) If the engine performs 25 cycles per second, how much gasoline is burnt in 1 hour? (e) How much power is generated by the engine per second in horsepower? (1 hp = 746 W)

Answer 1

Answer:

pls refer the attachment

Answer 2

Explanation:

In this question,

A heat engine getting energy from gasoline takes in 10000J and converts 2000J into work.

We need to find the following things-:

A)Efficiency of the heat engine- $\frac{work}{heat}$

Work = 2000J

Heat Input = 10.000J

Therefore efficiency of heat engine is = $\frac{2000}{10000}\times 100\%$

                                                               = $\frac{1}{5}\times 100\%$

                                                              = 20%

B)Heat released by the engine = Heat input - work

                                                    =10000 - 2000

                                                    =8000J

C)Gasoline burnt is each cycle = $\frac{10000}{5\times 10000}$

                                                   = $\frac{1}{5}$

                                                   = 0.2gm

D) Gasoline burnt in each cylce = 0.2

Therefore, gasoline burnt in 25 cycles = 25 × 0.2

                                                                =5gm

Hence Gasoline burnt in 1 second is 5gm

Therefore Gasoline burnt in 1 minute = 60 × 5

                                                             = 300gm

Gasoline burnt in 1 hour = 300 × 60

                                        = 18000gm

                                        =18k.g

E) Power generated by the engine per second = $10^{4}\times 5$ = $5\times 10^{4}W$

In horsepower = 67.02HP