When you price them online they list the weight and it seems it is about 2-3 lbs empty.
The weight of an empty backpack could probably be measured in grams. However, a filled backpack would best be measured in kilograms.
It depends where you lean, the weight of you and the backpack, and the distribution of weight within the backpack.
there was no food or water
It depends on its weight and the force of weight it is balencing out with.
They are roughly the same size as a normal school backpack. However, they can be a bit smaller as well. Also, they can be comparable to a hiking backpack.
Half of your weight is the estimated weight!
A day pack for Scouting can be a backpack, depending on the trip. A day trip consisting of mostly hiking can be a lighter weight backpack or a Camel backpack.
There is no weight in an empty balloon. Empty balloons will not stay on the ground long enough to have any real weight.
A school backpack should weigh less then 15 % of your body weight.
The Weight of an Empty Room was created in 2004.
The Internal Frame Backpack was invented by Greg Lowe in 1967. His novel series of straps made it possible to evenly distribute the weight of the backpack.
as a senior, mine is about 25 pounds.