Question

A pump discharges 700 𝑙𝑖𝑡𝑒𝑟𝑠 of fuel oil into a tank 25 𝑚 above the pump’s intake. How much work is done against gravity by the pump? One cubic centimeter of fuel oil has a mass of 0.89 g and one liter is 1,000 𝑐𝑚3.

Answer 1

$$m=(700)(1000)(0.89)=623000\ g=623\ kg$$

$$W=mgh=(623)(9.8)(25)=153\ kJ$$