Centripetal Force: Calculating Tension in Conical Pendulum

[kingyof2thejring]

Question 1
A conical pendulum consists of a string of length 1.2 m and a bob of mass 0.41 kg. The string makes an angle of 21° with the vertical. Calculate the tension in the string, in N.
iam not sure wat to do here if
$$l\omega{}^2 = \frac{g}{\cos\phi}$$
then i use
$$T=ml\omega{}^2$$ to get the force. is that the way to calculate the tension. Thanks in advance

 

[rocketboy]

Question 1
A conical pendulum consists of a string of length 1.2 m and a bob of mass 0.41 kg. The string makes an angle of 21° with the vertical. Calculate the tension in the string, in N.
iam not sure wat to do here if
$$l\omega{}^2 = \frac{g}{\cos\phi}$$
then i use
$$T=ml\omega{}^2$$ to get the force. is that the way to calculate the tension. Thanks in advance

First draw a diagram. I think you will see the answer when you do that.

(what would the tension be if it were straight down?)

 

[kingyof2thejring]

Tcos 0 = mg
T=4.30