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**[SOLVED] circular and projectile motion**

**1. Homework Statement**

In the Olympic hammer throw, contestants whirl a 7.3 kg ball on the end of a 1.2 m long wire before releasing it. Suppose the hammer is released frim a height of 1.3 m while moving in a direction 24 degrees above the horizontal. If it travels 84 m horizontally, what is its radial acceleration just before release.

The book answer is a = 892 m/s^2

**2. Homework Equations**

y = x tan theta - gx^2/2v0^2 cos^2 theta

a = v^2/r

**3. The Attempt at a Solution**

1.3 = 84 (.445) - 9.8 (84)^2/2v0^2 (.914)^2

v0^2 = 41386.8/36.1 = 1146.4

a = 1146.4/1.2 = 955 m/s^2

Even if I just use the velocity in the x direction, it does not work.