Question
For this problem, ignore air resistance.
You are to fire a rifle that shoots a particular bullet at 460 m/s at a target that is 45.7 m away and level with the rifle. Assuming that the acceleration due to gravity is 9.80 m/s², how high above the target must the barrel of the rifle be aimed such that the bullet hits the target?
You are to fire a rifle that shoots a particular bullet at 460 m/s at a target that is 45.7 m away and level with the rifle. Assuming that the acceleration due to gravity is 9.80 m/s², how high above the target must the barrel of the rifle be aimed such that the bullet hits the target?
Answers
bobpursley
The real question is how far the bullet falls vertically during the trip.
timeinair=45.7m/460m/s
how far does an object fall in that time?
h=1/2 g t^2
timeinair=45.7m/460m/s
how far does an object fall in that time?
h=1/2 g t^2
Steven
That's not entirely correct... That would only be true if the rifle was fired horizontally, giving the x component 460 m/s towards the target.
However, that 460 m/s has some UPWARD y component too, reducing the x component by some amount...
Thanks,
Steven
However, that 460 m/s has some UPWARD y component too, reducing the x component by some amount...
Thanks,
Steven
Damon
Forget that upward component. Too fast to be significant. look at 460 cos (angle up)
the cosine of your angle up will be essentially 1 and the sine will be about 0
the cosine of your angle up will be essentially 1 and the sine will be about 0
Steven
I would like to forget the upward component, as the object IS in fact a bullet fired at a fast velocity from a gun towards a target not too far away.
However, we're graded on the correctness of our problem solving. And, additionally, this factor WOULD become an issue if we were firing a marshmallow gun or a pea shooter at this distance, or if you were firing a sniper rifle at a target over a mile away.
Thanks,
Steven
However, we're graded on the correctness of our problem solving. And, additionally, this factor WOULD become an issue if we were firing a marshmallow gun or a pea shooter at this distance, or if you were firing a sniper rifle at a target over a mile away.
Thanks,
Steven