p13_016.pdf

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Chapter 13 - 13.16

16. (a) Analyzing vertical forces where string 1 and string 2 meet, we ﬁnd

T 1 =

40N

cos35 ◦

=49N .

(b) Looking at the horizontal forces at that point leads to

T 2 = T 1 sin35 ◦ = (49N)sin35 ◦ =28N .

(c) We denote the components of T 3 as T x (rightward) and T y (upward). Analyzing horizontal forces

where string 2 and string 3 meet, we ﬁnd T x = T 2 = 28N. From the vertical forces there, we

conclude T y = 50N. Therefore,

(d) The angle of string 3 (measured from vertical) is

θ =tan − 1 T x

T y

=tan − 1 28

50

=29 ◦ .

T 3 = T x + T y =57N .