A mass of 15kg is supsended by 2 cords from a ceiling. the cords have lenghts of 15cm and 20cm, and the distance between the points wheere they are attached on the ceiling ia 25cm. determine the tension in each of the 2 cords.

can someone please tell me the steps to take inorder to solve this question. Thanks in advance:)

2 answers

Draw a position diagram showing the cords
by cosine law, find the angle between the 25 and 20 cm cords
15^2 = 25^2 + 20^2 - 2(25)(20)cosß
ß = 36.87º

AHHH, just realized our triangle is right-angled since 25^2 = 15^2+20^2
so the other angle is 53.13º , lucky.

Now draw a vector diagram with a vertical line to represent the 15 kg,
from the top of that vertical line draw a line parallel to the 15 cm cord, and from the bottom of the vertical line, draw a line parallel to the 20 cm cord until they meet.
This should also be a right-angled triangle with the top angle 53.13, and the bottom angle 36.87 and 15 as the hypotenuse
Let T1 be the tension in the 15 cm cord and T2 the tension in the 20 cm cord
cos 53.13 = T1/15
T1 = 9 kg

and in the same way
T2 = 15 cos 36.87 = 12 kg
If anyone is lost with the Reiny's answers, you just convert the kilo answers to newtons. m*g = kg*9.81m/s^2 kinda thing