Solving projectile motion problems with trigonometry

[thugg]

i can't remember how to do this at all, but can someone just post a simple step by step solution for this? thanks

http://img275.imageshack.us/img275/2392/ss2mx.jpg




also having trouble with this one



http://img374.imageshack.us/img374/1146/dfsd4mu.jpg

 

[Fermat]

Q1: resolve T1 into horizontal and vertical components. Then equate all the horizontal forces and all the vertical forces.

 

[Fermat]

Q2: let T1 be the tension in the angled rope/string and T2 be the tension in the horizontal rope/string. Use the same strategy as for Q1 to solve for T1 and T2. Hence get coefft of friction

 

[thugg]

hmm still kinda confused, any chance you could show me step by step how to solve it


like how do you resolve T1 and T2 to get values...like i know the 20 has components of x = 0, and y = -20 right? but how do u get values with the 30 degree angle?

 

[teclo]

hmm still kinda confused, any chance you could show me step by step how to solve it


like how do you resolve T1 and T2 to get values...like i know the 20 has components of x = 0, and y = -20 right? but how do u get values with the 30 degree angle?

draw out the angles and use trig.

T1+T2=(0,+20)

use the sin and cos function to resolve the two tensions into vectors. you should have 2 sets of equations to solve for T1 or T2, once you know one the other is only a matter of substitution.