Air bags are designed to deploy 30 cm in 12 ms. Estimate the acceleration of the front surface of the bag as it expands. Express your answer in terms of the acceleration of gravity g.
2007-01-18 16:41:51 · 4 answers · asked by eureka4sureka 1 in Science & Mathematics ➔ Physics
So if we convert the 30 cm to m --> 0.3m
Now, divide the distance by the time it takes to get there, in seconds. 0.3 m / 0.012 sec = 25 m/sec.
So if we want to figure the average acceleration, and it would take a second at that rate to reach 25m/sec, then we can guess the acceleration to be 25 m/sec^2.
So how does gravity rear its ugly head? The acceleration due to gravity on earth is 9.8 m/sec^2. You can use the calculator, but if we're estimating then its (about) 25 m/sec^2 / 10 m/sec^2, or roughly 2.5 times the acceleration of gravity.
What the teacher is looking for here is the statement that it corresponds to about 2.5 g's.
2007-01-18 16:58:35 · answer #1 · answered by Richard B 4 · 0⤊ 1⤋
whoa!
Seriously. This can't be a homework question, right?
The expansion will not really have anything to do with
gravity. You can estimate an average velocity with the
information you gave, but not any instantaneous velocity
at any time and thus you cannot determine acceleration.
Gravity is NOT involved in any significant way.
EDIT:
PLEASE don't pay attention to the guy two below me.
His answer is dead wrong. Nothing you said says the bag
will deploy in one second. That is what his answer depends on.
There is not enough information in your question to answer it.
2007-01-19 00:47:29 · answer #2 · answered by Anonymous · 0⤊ 0⤋
divide ,3/12 * 10^-3 ---veloc
divide the answer above by 0.012 ----accel
then divide that by 10 ( in terms of g)
the guy above has assumed the 1s wrong
ud be dead in that time
2007-01-19 01:04:01 · answer #3 · answered by El C 2 · 0⤊ 1⤋
No wonder people with college degrees earn more money. My brain hurts just thinking about that.
2007-01-19 00:50:00 · answer #4 · answered by Anonymous · 0⤊ 0⤋