A12 v car battery is rated at 100 ah (ampere-hours). how many times could a 0.8 kw camping kettle be boiled, if it takes an average of 5 minutes to boil the kettle?

18 times

We are given;

We are required to calculate the number of times the kettle can be boiled.

Energy = Voltage × Current × time

Voltage = 12 V

Current = 100 Amperes

Time - 1 hour or 3600 sec

Therefore;

Energy from the battery = 12 V × 100 A × 3600 sec

                                        = 4,320,000 Joules

Energy = Power × time

In this case;

Power is 0.8 kW or 800 watts

Time = 5 mins or 300 seconds

Therefore;

Energy required to boil a kettle

 = 800 watts × 300 seconds

 = 240,000 Joules

We divide the total amount of energy from the battery by the energy needed to boil one kettle.

Number of times = 4,320,000 Joules ÷  240,000 Joules

                            = 18 times

Therefore, the kettle can be boiled 18 times using energy from the battery.