HOW TO TROUBLESHOOT LAPTOP BATTERY CHARGER?

You’re at 25,000 feet and the flight attendant informs the passengers that they can use electronic devices. You slowly remove the laptop from its case and put it on the seatback table. When you hit the power button, it is as lifeless as that cold airline tuna sandwich. If you are not anywhere near the wall-socket then the problem maybe on the battery itself or perhaps the battery charger, also