Answer:
Answered
Explanation:
The radius of curvature of the mirror R = 20 cm
then the focal length f = R/2 = 10 cm
(a) From mirror formula
1/f = 1/di + /1do
then the image distance
di = fd_o / d_o - f
= (10)(40) / 40-10
= 30.76 cm
since the image distance is positive so the image is real
ii) when the object distance d_0=20 cm
di = 10×20/ 20-10
= 20
Hence, the image must be real
iii)when the object distance d_0 = 10
di = 10×10 / 10-10 = ∞ (infinite)
the image will be formed at ∞
here also image will be real but diminished.
Explanation:
speed of wave
v = wavelength x frequency
since frequency is f = 1/Period then
v = wavelength : Period
v = 10 cm/ 0.2 s = 50 cm/s
v = 0.5 m/s
Answer:
The floor of the ocean is 6120 m deep.
Explanation:
In order to find the depth of the ocean we need to use the speed of the ultrasonic sound 1530 m/s and the time it takes for the echo to comeback. Since the wave is transmitted by the vessel goes to the bottom of the ocean and comeback, it travels the distance between the vessel and the floor two times, so we can divide the time by two. We then have:
D = V*t/2 = 1530*8/2 = 1530*4 = 6120 m
The answer is 100.
The formula is KE = 1/2mv^2
Then you plug in 50 to the m
And 2 to the v . That’s how I got 100 .
Hope this helps
Answer:
a) {[1.25 1.5 1.75 2.5 2.75]
[35 30 25 20 15] }
b) {[1.5 2 40]
[1.75 3 35]
[2.25 2 25]
[2.75 4 15]}
Explanation:
Matrix H: {[1.25 1.5 1.75 2 2.25 2.5 2.75]
[1 2 3 1 2 3 4]
[45 40 35 30 25 20 15]}
Its always important to get the dimensions of your matrix right. "Roman Columns" is the mental heuristic I use since a matrix is defined by its rows first and then its column such that a 2 X 5 matrix has 2 rows and 5 columns.
Next, it helps in the beginning to think of a matrix as a grid, labeling your rows with letters (A, B, C, ...) and your columns with numbers (1, 2, 3, ...).
For question a, we just want to take the elements A1, A2, A3, A6 and A7 from matrix H and make that the first row of matrix G. And then we will take the elements B3, B4, B5, B6 and B7 from matrix H as our second row in matrix G.
For question b, we will be taking columns from matrix H and making them rows in our matrix K. The second column of H looks like this:
{[1.5]
[2]
[40]}
Transposing this column will make our first row of K look like this:
{[1.5 2 40]}
Repeating for columns 3, 5 and 7 will give us the final matrix K as seen above.
