Answer:
1) In a concave mirror parallel rays falling on it converges at F and 2F.
Explanation:
Spherical mirrors can be used for magnification of images. There are basically two types of spherical mirrors and they are converging mirror and diverging mirrors. The converging mirrors are also termed as concave mirrors and its basic work is to converge or combine light rays coming from a larger distance to a single point. Mostly the light beams falling parallel to the principle axis of the concave mirror will be acting as parallel rays. And when these parallel rays fall on the mirror, the converging point can be the focal point of the mirror.
Thus the location of converging point in concave mirrors will be based on the position or distance of object from the mirror. If the object distance is very far from the twice the focal length distance of mirror, then the converging point will be the focal point or F. And if the object is placed slightly greater than twice the distance of focal point, then the image will be obtained at 2F. But the parallel beams will be converging at F and 2F.
Answer:
The resultant velocity is 86.1 mi/h.
Explanation:
The law of cosines is given by:

Where:
c: is the resultant velocity =?
a: is the velocity of the plane = 75.0 mi/h
b: is the velocity of the wind = 15.0 mi/h
θ: is the angle between "a" and "b"
The angle between "a" and "b" can be found as follows:
Now, by using the law of cosines we have:

Therefore, the resultant velocity is 86.1 mi/h.
The law of sines is:

Where:
γ: is the angle between "b" and "c"
α: is the angle between "a" and "c"
So, if we want to find "c" by using the law of sines, we need to know another angle besides θ (γ or α), and the statement does not give us.
I hope it helps you!
<span>Divergent plate boundaries are locations where plates are moving away from one another. This occurs above rising convection currents. The rising current pushes up on the bottom of the lithosphere, lifting it and flowing laterally beneath it. This lateral flow causes the plate material above to be dragged along in the direction of flow. At the crest of the uplift, the overlying plate is stretched thin, breaks and pulls apart. hope this helps
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The correct answer is A. 250N
Work is a product of force and distance.
That is, work done=force×distance
Therefore substituting for the values in the question:
500J=force×2m
force= 500Nm/2m=250N
another unit for work done is Nm as force as the SI unit of force is newtons and distance in meters