# Physics

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?

1. 👍 0
2. 👎 0
3. 👁 479
1. 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

1. 👍 0
2. 👎 0
2. 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

1. 👍 0
2. 👎 0
posted by Steven
3. 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

1. 👍 0
2. 👎 0
posted by Damon
4. 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

1. 👍 0
2. 👎 0
posted by Steven

## Similar Questions

1. ### physics

A rifle that shoots bullets at 460 m/s is to be aimed at a target 47.0 m away. If the center of the target is level with the rifle, how high above the target must the rifle barrel be pointed so that the bullet hits dead center?

asked by tom on November 3, 2010
2. ### Physics

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

asked by Steven on October 7, 2010
3. ### Physics

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

asked by Steven on October 6, 2010
4. ### Physics

An observer stands 25 m behind a marksman practicing at a rifle range. The marksman fires the rifle horizontally, the speed of the bullets is 840 m/s, and the air temperature is 20 °C. How far does each bullet travel before the

asked by Anonymous on April 26, 2015
5. ### Physics

An observer stands 43.0 m behind a marksmen practicing at a rifle range. The marksman fires the rifle horizontally which gives the speed of the bullet to be 939 m/s. How far does each bullet travel before the observer hears the

asked by Steph on March 13, 2011
1. ### physics

A rifle with a muzzle velocity of 480 m/s shoots a bullet at a target 45.6 m away. How high above the target must the rifle barrel be pointed to ensure that the bullet will hit the target? Neglect air resistance.

asked by Will on September 7, 2014
2. ### Science: Physics

A physics teacher shoots a .30 caliber rifle at a 0.47 kg block of wood. The rifle and wood are mounted on separate carts that sit atop an air track (like a linear air hockey table--ie. frictionless). The 5.7 kg rifle fires a 27

asked by Joan on January 6, 2011
3. ### Physics

The fastest bird is the spine-tailed swift, which reaches speeds of 171 km/h. Suppose that you wish to shoot such a bird with a 22-caliber rifle that fires a bullet with a speed of 366 m/s. If you fire at the instant when the bird

asked by Shelagh on November 23, 2011
4. ### Physics

An airplane is flying horizontally with a constant velocity of 160 m/s at an altitude of 5100 m when it releases a package. a. How long does it take for the package to reach the ground? (Ignore air resistance.) b. What is the

asked by JP on September 19, 2012
5. ### Math - Calculus

The horizontal velocity is constant. (Ignore air resistance.) Recall from your study of trigonometry that if you release a rock at a speed v in a direction that makes an angle α with the horizontal, then the initial vertical

asked by Jamie on February 14, 2017

More Similar Questions