Question

By burning 1 g of coal, the energy produced is 2 kcal. Then for 1 kWh, the quantity of coal so required will be nearly –

• A. 9 kg
• B. $\frac { 4 } { 5 }$ kg
• C. $\frac { 3 } { 7 }$kg
• D. $\frac { 3 } { 14 }$ kg

Answer 1

Answer: (C)

$\frac { 3 } { 7 }$kg

Answer 2

Amount of coal required

= $\frac { 3600 } { 4.8 } \times \frac { 1 } { 2 }$ = 430 gm

= $\frac { 430 } { 1000 }$ kg » 3/7 kg