1) Focal length
We can find the focal length of the mirror by using the mirror equation:

(1)
where
f is the focal length

is the distance of the object from the mirror

is the distance of the image from the mirror
In this case,

, while

(the distance of the image should be taken as negative, because the image is to the right (behind) of the mirror, so it is virtual). If we use these data inside (1), we find the focal length of the mirror:

from which we find

2) The mirror is convex: in fact, for the sign convention, a concave mirror has positive focal length while a convex mirror has negative focal length. In this case, the focal length is negative, so the mirror is convex.
3) The image is virtual, because it is behind the mirror and in fact we have taken its distance from the mirror as negative.
4) The radius of curvature of a mirror is twice its focal length, so for the mirror in our problem the radius of curvature is:
Answer:
Here is my answer...
Explanation:
The cart will connect with the opposite force, and then the cart will come to a shuddering stop before moving in the direction of the oposite force.
Hope I helped! :)
Answer:
Newton's law of universal gravitation states that every particle attracts every other particle in the universe with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.
Explanation:
To develop this problem it is necessary to apply the concepts related to the Dopler effect.
The equation is defined by

Where
= Approaching velocities
= Receding velocities
c = Speed of sound
v = Emitter speed
And

Therefore using the values given we can find the velocity through,


Assuming the ratio above, we can use any f_h and f_i with the ratio 2.4 to 1


Therefore the cars goes to 145.3m/s