If it is a car battery (as given in the category) it is reasonably safe to assume that under load it is about 12V.
I = P/E = 168W / 12V = 14A
T = 200AH / 14A = 14.29H
However it would be entirely different for a different battery.
This is also assuming that the car battery is not being charged at any time while the load is present.
If you draw 280mA continuously, the battery will last 1 hour. 140mA continuous use will last 2 hours and so on.
It stands for watt-hour. In relationship to batteries, it measures how many watts in an hour a battery can sustain. A 63 watt-hour battery will supply 63 watts for 1 hour, or 6.3 watts for 10 hours or 31.5 watts for 2 hours, etc. It is extremely difficult to determine, from this number, how long your equipment (say, a laptop) will run using a 63 hour battery. The thing for which this number is most useful is battery comparison. A 20 WHr battery will last twice as long as a 10 WHr battery and half as long as a 40 WHr battery and so on.
It depends on how much drain is placed on the battery !
To answer this question the amp/hours of the battery must be stated.
Up to 2 or 3 hours
lun times
V is the batteries rated voltage. Ah is the amp-hour of the battery. This is a rating of how many amps it can supply for a given period of time. For example a 600 Ah battery with a 100 A load means that the battery should last 6 hours.
A typical deep cycle battery usually has amp-hour ratings ranging from 50 to 200 amp-hours.
A 600 mAh battery can produce 75 mA for about 8 hours. If it is called upon to deliver 600 mA, it will last somewhat less than one hour. This is because ampere-hour ratings for batteries are, by standard agreement, normalized to an eight-hour rate. The actual rating is only a comparative rating, so you could properly say that a 900 mAh battery, for instance, will last 1.5 times longer than a 600 mAh battery.
The average Canon camera battery lasts for about 2 to 4 hours, depending on the model and usage.
A 300 ampere-hour battery can supply 300 amperes for somewhat less, sometimes substantially less, than one hour. It might not even be rated to provide 300 amperes at all. It depends on the battery. The reason for this is that ampere-hour ratings are, by definition, normalized to an eight-hour rate. This means that you can pull 300/8, or 37.5 amperes from that battery for 8 hours. That is the reference point. If you were, for instance, to pull 18.75 amperes, you would expect the battery to last somewhat longer than 16 hours, and if you pulled 75 amperes, you would expect the to last somewhat less than 4 hours, both from a full charge, and both from a recently equalized state. You need to check the published discharge curve for the batter to know for sure.
it doesnt matter what type of computer you have, it depends on how long the battery in your computer lasts. there r many different types of batterys. some last a couple hours, and some last up to 6 hours.