Answer:
Step-by-step explanation:
<u>Scientific notation</u>
where:
is any positive or negative <u>whole number</u>.
To convert a number into scientific notation, <u>move</u> the decimal point to the <u>left or right</u> until there is <u>one digit</u> to the left of the decimal point.
The number of times you have moved the decimal point is .
- If the decimal point has moved to the <u>left</u>, is positive.
- If the decimal point has moved to the <u>right</u>, is negative.
To convert 500,000,000,000 into scientific notation, move the decimal point <u>11 places to left</u>, so a = 5. As we have moved the decimal point 11 places to the left, the exponent "n" is 11 and is <u>positive</u>.
To convert 0.00000000005 into scientific notation, move the decimal point <u>11 places to the right</u>, so a = 5. As we have moved the decimal point 11 places to the right , the exponent "n" is 11 and is <u>negative</u>.
Learn more about scientific notation here:
brainly.com/question/28235385
Givens
<em><u>Slower car</u></em>
r = r
t = 12 hours
d = ?
<em><u>Faster car</u></em>
r = r + 20
t = 8 hours
d = ?
It doesn't matter what the exact distance is. You just have to know that the 2 distances are equal ie going to the mountains from his home is the same distance as going from the mountains to his home.
d = r * t
r * 12 hours = (r + 20)* 8 hours. Remove the brackets on the right
r*12 = 8r + 20*8
r*12 = 8*r + 160
r*12 - 8r = 8r - 8r + 160
4r = 160
r = 40 miles / hour
=================
Slower Ride determines the distance.
d = r*t
d = 40 * 12
d = 480
Check
Use the faster rate (r + 20) = 40 + 20 = 60 mph
60 * 8 = 480. Both distances work out to be the same.
OK, so the graph is a parabola, with points x=0,y=0; x=6,y=-9; and x=12,y=0
Because the roots of the equation are 0 and 12, we know the formula is therefore of the form
y = ax(x - 12), for some a
So put in x = 6
-9 = 6a(-6)
9 = 36a
a = 1/4
So the parabola has a curve y = x(x-12) / 4, which can also be written y = 0.25x² - 3x
The gradient of this is dy/dx = 0.5x - 3
The key property of a parabolic dish is that it focuses radio waves travelling parallel to the y axis to a single point. So we should arrive at the same focal point no matter what point we chose to look at. So we can pick any point we like - e.g. the point x = 4, y = -8
Gradient of the parabolic mirror at x = 4 is -1
So the gradient of the normal to the mirror at x = 4 is therefore 1.
Radio waves initially travelling vertically downwards are reflected about the normal - which has a gradient of 1, so they're reflected so that they are travelling horizontally. So they arrive parallel to the y axis, and leave parallel to the x axis.
So the focal point is at y = -8, i.e. 1 metre above the back of the dish.
Answer:
3150mm
Step-by-step explanation:
1cm is 10mm you convert it then times it together l x b x h will equal 3150
