A rifle is fired in a valley with parallel vertical walls. The echo from one wall is heard 1.55 s after the rifle was fired. The
1 answer:
Answer:
Explanation:
Given:
velocity of the sound,
time lag in echo form one wall of the valley,
time lag in echo form the other wall of the valley,
<u>distance travelled by the sound in the first case:</u>
Since this is the distance covered by the sound while going form the source to the walls and then coming back from the wall to the source so the distance of the wall form the source will be half of the distance obtained above.
<u>distance travelled by the sound in the second case:</u>
Since this is the distance covered by the sound while going form the source to the walls and then coming back from the wall to the source so the distance of the wall form the source will be half of the distance obtained above.
<u>Now the width of valley:</u>
You might be interested in
Answer:
d = 1.19 m
Explanation:
Given that,
The force applied by the ball, F = 39.6 N
The work done on the catchers glove is 47.5 J
We need to find the distance traveled by the ball. We know that,
Work done, W = Fd
Where
d is the distance traveled
So, it will cover 1.19 m.
Answer:
The rifle barrel must be pointed at a height of 4.45cm above the target so that the bullet hits dead center.
Explanation:
First, we need to sketch the situation so we can have a better idea of what the problem looks like (Refer to uploaded picture).
So as you may see in the drawing, when pointing the rifle to the target, we can see it as a triangle, but in reality, the bullet will have a parabolic trajectory. Both points of view will help us determine what the height must be. In order to find it, we need to first determine at what angle the bullet should be shot. In order to do so we can use the range formula, which looks like this:
Where R is the range of the bullet (this is how far it goes before it has the
same height it was shot from), v is the original speed of the bullet, θ is the angle at which the bullet is shot and g is the acceleration of gravity.
We can solve this equation for theta, so we get:
so now we can substitute the given data:
so we get:
θ=0.05614°
once we get the angle, we can look at the triangle diagram. From the drawing we can see that we can use the tan function to find the height:
so we can solve this for h, so we get:
which yields:
or
