Let's use the mirror equation to solve the problem:

where f is the focal length of the mirror,

the distance of the object from the mirror, and

the distance of the image from the mirror.
For a concave mirror, for the sign convention f is considered to be positive. So we can solve the equation for

by using the numbers given in the text of the problem:



Where the negative sign means that the image is virtual, so it is located behind the mirror, at 8.6 cm from the center of the mirror.
First, calculate the work done: 54 x 10 = 540J.
Now calculate power: 540 / 6 = 90.
The answer is 90W.
Hope this helps.
Answer:
Length, l = 33.4 m
Explanation:
Given that,
Electrical field, 
Let the electrical potential is, 
We need to find the length of a thundercloud lightning bolt. The relation between electric field and the electric potential is given by :

So, the length of a thundercloud lightning bolt is 33.4 meters. Hence, this is the required solution.
<span>Answer:
So this involves right triangles. The height is always 100. Let the horizontal be x and the length of string be z.
So we have x2 + 1002 = z2. Now take its derivative in terms of time to get
2x(dx/dt) = 2z(dz/dt)
So at your specific moment z = 200, x = 100âš3 and dx/dt = +8
substituting, that makes dz/dt = 800âš3 / 200 or 4âš3.
Part 2
sin a = 100/z = 100 z-1 . Now take the derivative in terms of t to get
cos a (da./dt) = -100/ z2 (dz/dt)
So we know z = 200, which makes this a 30-60-90 triangle, therefore a=30 degrees or π/6 radians.
Substitute to get
cos (Ď€/6)(da/dt) = (-100/ 40000)(4âš3)
âš3 / 2 (da/dt) = -âš3 / 100
da/dt = -1/50 radians</span>
Answer:
A. 12,240.
Explanation:
1,530 times 8.0 = 12,240.
hope this helped :)