This preview shows page 1. Sign up to view the full content.
Unformatted text preview: 2 ⎤
= 45
θ = 360 ⎢1 −
2
2⎥
⎣ π (R − r ) ⎦ Prob.2 (10 pts.). The area of the triangle DEC is one half of the area of triangle ABC. CG
is perpendicular to both AB and DE. If CF = 5.0 cm and GB = 10.0 cm, what is the value
of CE?
C D E
F A B
G AREA of DEC =
get 1
1
11
(CF × DE ) = AREA of ABC =
(CG × AB) from which we can
2
2
22 1 DE CF
=
2 AB CG
2 1 ⎛ CF ⎞
DE CF
By similarity of triangles
so that = ⎜
=
⎟ or CG =
2 ⎝ CG ⎠
AB CG
1
CF FE
CF
Also by similarity
or FE = GB
= 10 cm
=
CG GB
CG
2
Finally by the Pythagorean Theorem we get:
CE = FE 2 + CF 2 = (10.0 cm 1 )2 + (5.0 cm )2 = 8.7 cm
2 2 × 5.0 cm...
View
Full
Document
This test prep was uploaded on 04/05/2014 for the course PHYS 100 taught by Professor Dech during the Fall '08 term at Drexel.
 Fall '08
 Dech
 Physics

Click to edit the document details