Question

Life of a component under heavy load alone is 100 Hrs while under normal load, it is 1000 hrs. How many hours it can be operated at normal load, if it is found to be operated for 10 hrs at heavy load?

• A. 600 Hrs
• B. 900 Hrs
• C. 700 Hrs
• D. 800 Hrs

Answer 1

The correct option is B 900 Hrs

Heavy load = ${\sigma }_1$

$L_1=100hrs$

Normal load = ${\sigma }_2$

$L_2=1000hrs$

$n_1=10hrs$ (hours of operation under heavy load)

$n_2?$ (hours of operation under load)

$\Rightarrow \frac{n_1}{L_1}+\frac{n_2}{L_2}=1$

$\Rightarrow \frac{10}{100}+\frac{n_2}{1000}=1$

$n_2=900hrs$