Question

Assuming a 25% efficiency, how many Calories would a horse need to consume to work at 1.0 hp for 2.0 hh ?

Answer 1

Answer:

E = 7.11 × $10^{-7}$  Cal

Explanation:

given data

efficiency = 25 %

solution

first we get here E by the power that is express as

p = $\frac{E}{t}$     ...........1

E = p × t

E = 1 ×  2 × $\frac{1hp}{746w} \times \frac{1hr}{3600 s}$  

E = 7.447 × $10^{-7}$ J

and

Ein is get by efficiency

Ein = $\frac{Eout}{\eta }$        ..................2

Ein = $\frac{7.447 \times 10^{-7}}{.25 }$

Ein = 29.788 × $10^{-7}$  J

so required energy is

E = 29.788 × $10^{-7}$  ×  $\frac{1Cal}{4.184J}$

E = 7.11 × $10^{-7}$  Cal