Physics---polar coordinate system word problem HELP ME please?

Question

A point is located in a polar coordinate system by the coordinates r=2.5m and --this symbol is a zero with a horizontal line through it...I don't know what it means but that equals 35 degrees. Find the x and y coordinates of this point, assuming the two coordinate systems have the same origin.

I don't really know what the question is asking. Please give me an explanation I don't want just the answer.

first I drew an angle with a side that was 2.5m and the angle was 35 degrees...is that right so far..?

okay and then I have no clue of what I have to do after that.


one more question
does anyone know what 10 to the 21st is called. I tried to look it up but I couldn't find anything.

Thanks a lot

Answer 1

10^21

1,000,000 = 1 million = 10^6
10^9=billion
10^12 = trillion
10^15 = quadrillion
10^18 = quintillion
10^21 = SEXtillion (yes, that's the word. It means '6', just like a band with 6 people is called a sextet.)

This, of course, is the US version.

The Brits call this 1000 trillion (they go up by powers of 6, not 3).

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Polar coordinates looks like a bulls-eye target or dart board. 0 degrees starts at the center and goes to the right. Angular measurement starts at the 0 degree line and goes counter clockwise.

The 0 with a line thru it is the Greek letter theta. It measures the angle with regard to the 0 degree line. So, an angle with theta = 35 degrees is slightly above the 0 line. r=2.5m means that the displacement from the center is 2.5 meters, to the right and slightly up.

Now, the x,y coordinates for that point would make a triangle with one side along the x-axis, one parallel with the y-axis and one the hypotenuse of a right triangle. The hypotenuse would be 2.5m.

The x coordinate would be 2.5(cos 35)m. The y coordinate would be 2.5(sin 35)m.

Answer 2

the "zero with a horizontal line through it" is called Theta. Theta is a greek letter that usually pertains to an angle.


Your drawing sounds correct, but make sure one of your lines is horizontal in the 0 degree direction. your other line should be 35 degrees counterclockwise of that (for a correct polar graph). After that draw a perpendicular line to the horizontal axis to complete a right triangle. Then use trig to solve for the other sides of the right triangle, then you have your (X,Y) Coordinate...


x = 2.5 cos (35) ~ 2.05
y = 2.5 sin (35) ~1.43

so it's coorisponding cartesian coordinate is (2.05,1.43)
or to be more exact ( 2.5cos35, 2.5sin35)

Answer 3

Splatt is only kinda right. In the UK, the billion used to be a million miliions, but that is long gone in science and maths circles. We now use 10^9 as a billion and go up in powers of 3 not 6, just like the rest of the uncivilised world! Seems like the French aren't sure and keep changing their minds! How typically French! ;o)