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: The answer is A
Explanation: The bumper is the first part of an automobile to be impacted when in a head-on accident
Answer:
In a magnet, the domains all point in the same direction; in an ordinary piece of metal, they're all jumbled up.
Explanation:
In a magnet, the domains all point toward the north pole; in an ordinary piece of metal, they all point to the south pole.
Side note:
Hope this helps!
Please give Brainliest!
彼が好きな男のような話は妻と関係があったのでそう
Explanation:これが難しい場合はコメントで教えてくださいが何でも
lol okay
from: a random person :)
The work done to pull the sister back on the swing is equal to the increase in potential energy of the sister:

(1)
where m is the sister's mass, g is the gravitational acceleration and

is the increase in altitude of the sister with respect to its initial position.
By calling

the angle of the chain with respect to the vertical, the increase in altitude is given by

(2)
where L is the length of the chain.
Putting (2) inside (1), we find

from which we can find the mass of the sister: