Question

Find the work done by the force F=10i+15j in moving an object from P(0,0) to Q(2,3).

Answer 1

What is the distance between P(0,0) and Q(2,3)?

Answer 2

Yeah I think so...(2,3)?

Answer 3

Sorry, \[W = F*d\]

Answer 4

My son is playing some silly video game in the background and it is destroying my brain :-)

Answer 5

Distance between two points \((x_1,y_1)\) and \((x_2,y_2)\) is given by \[d = \sqrt{(x_1-x_2)^2 + (y_1-y_2)^2}\]

Answer 6

Haha no problem (:

Answer 7

easy, because one of the points is (0,0)!

Answer 8

Yeah that wasnt so bad... I got square root of 1

Answer 9

;-( how?

Answer 10

wait was that formula supposed to be x1-y1 and x2-y2?

Answer 11

No, I wrote it like I meant it. It's the Pythagorean theorem, in disguise

Answer 12

Okay so I did square root of (0-0)^2 + (2-3)^2 is that right?

Answer 13

Nope. \((x_1,y_1) = (0,0)\) and \((x_2,y_2) = (2,3)\)

Plug into formula\[d = \sqrt{(x_1-x_2)^2 + (y_1-y_2)^2}\]

Answer 14

\[d = \sqrt{(0-2)^2 + (0-3)^2} = \]

Answer 15

Alright now I got square root 13 haha

Answer 16

Woah sorry about that huge space hahaha my computers crazy

Answer 17

just Pythagorean theorem, as I said

Answer 18

\[d=\sqrt{13}\] is correct

Answer 19

Now I think we find the magnitude of the force vector, and multiply it by \(d\) to get our answer

Answer 20

Okay Ill do that now

Answer 21

Alright I got 18

Answer 22

and then when I multiply them together would it just be 18 square root 13

Answer 23

How did you get 18?

Answer 24

square root of 10^2 +15^2?

Answer 25

oh or would it just be square root of 18?

Answer 26

\[\sqrt{10^2+15^2} = \sqrt{100+225} = \sqrt{325} = \sqrt{25*13} = 5\sqrt{13}\]

Answer 27

Now we multiply \(d = \sqrt{13}\) by \(||F|| = 5\sqrt{13}\) and get \(W = \)

drum roll please....a hush falls over the crowd...will she get it?

Answer 28

Umm 65? :D

Answer 29

the crowd goes nuts!!!

Answer 30

Yayyyyy thank you! I think my brain is fried but I understand everything a lot better now! (:

Answer 31

Come on back, let's finish off the cube root problem...

Answer 32

Okay haha Ill try to do it quick because I have to go to bed :P