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## Homework Statement

In the device shown below, a 1.75 kg ball suspended by two cords is whirled around in a circle of radius 95 cm. The ball makes 10 revolutions in 2 seconds. Find the tension in each of the two cords (remember: the tension in each cord acts toward the pole).

View attachment 29633

Well...the attachment isn't quite working...so I'll attempt to draw the picture...

|..\ <--This angle 30 degrees

|...\ <--Cord 1

|.....\

|......O <- Ball.....................Radius from ball to pole = .95 meters (95 cm)

|....../................................Angle of cords are both 30 degrees from the pole.

|...../ <--Cord 2..................Mass of ball is 1.75 kg

|..../

|.../ <--This angle 30 degrees

|./

^

Pole

## Homework Equations

Fc = mV^2/r

Vt=2pi r/T

Fg=mg

F=ma

Ftx=Ftsin theta

Fty=Ftcos theta

## The Attempt at a Solution

r=.95m

T=.2 seconds

Fty1-Fty2=Fg

Ft1cos30 - Ft2cos210 = 1.75kg x 9.8 m/s^2

Ft1+Ft2=19.8

Ftx1+Ftx2=Fc

Ft1sin30 + Ft2sin210 = m((2 pi r)/T)^2 / r

.5Ft1 - .5Ft2 = 1.75kg x (29.85 m/s)^2 / .95m

.5Ft1 - .5Ft2 = 1640.82N

Ft1 - Ft2 = 3281.64N

Ft1 = 19.8 - Ft2

19.8 - 2Ft2 = 3281.64N

Ft2 = -1630.92N

Ft1 = 1650.72N

I'm not sure if what I did is completely right. Please help. Thanks!