Question

Calculate month cost of using 50W energy saver for 8 hours daily and two electric fan of 100W for 10 hours daily, if the price of a unit is Rs15

Answer 1

Answer:-

Case-1:-

• Power=50W=P
• Time=8h=t.
• Work done =W

We know that

$\boxed{\sf W=Pt}$

$\\ \sf\longmapsto W=50\times 8$

$\\ \sf\longmapsto W=400wh$

Case-2:-

• Power of one fan=100w
• Power of two fan=100w+100w=200w
• Time=10h

$\\ \sf\longmapsto W=Pt$

$\\ \sf\longmapsto W=200\times 10$

$\\ \sf\longmapsto W=2000wh$

Now

Total work done

$\\ \sf\longmapsto W_{net}=2000+400=2400wh$

$\\ \sf\longmapsto W_{net}=2.4units$

Cost per unit=Rs15

$\\ \sf\longmapsto Cost=2.4\times 15$

$\\ \bf{\boxed{\bf{\longmapsto Electricity\:bill=Rs36}}}$