# Calculating Radial Acceleration in Olympic Hammer Throw

• physic1GUY
In summary, the conversation discusses a problem involving the Olympic hammer competition. The competitor turns a 7.3 kg ball at the end of a 1.2 meter metal cable and throws it at a 21 ° angle above the horizon. The hammer travels a horizontal distance of 83 meters before being released. The goal is to calculate the radial acceleration of the hammer just before liberation. Using the path equation and solving for time, the initial velocity is found to be 103.69 m/s, which can then be used to calculate the centripetal acceleration with the equation a=v^2/r. The conversation also mentions the need to refer to the mass in the calculations.
physic1GUY

## Homework Statement

confession Olympic hammer competition, competitor turns mass 7.3 kg ball at the end of a metal cable length 1.2 meters. Throw the hammer was released some 1.3 meters high 21 ° angle above horizon.
Last horizontal distance was 83 m hammer, what is the radial acceleration of the hammer just before liberation?

## Homework Equations

Path equation - y=xtanTHETA - g / (2v0^2cos^2THETA) x x^2

## The Attempt at a Solution

i set the details i know at the equation and i got a huge velocity 103.69 m/s
i put it in the equation a=v^2 / r but this is an astronom acceleration
what did i do wrong , i will glad for help and explanation...
thanks!

physic1GUY said:

## Homework Statement

confession Olympic hammer competition, competitor turns mass 7.3 kg ball at the end of a metal cable length 1.2 meters. Throw the hammer was released some 1.3 meters high 21 ° angle above horizon.
Last horizontal distance was 83 m hammer, what is the radial acceleration of the hammer just before liberation?

## Homework Equations

Path equation - y=xtanTHETA - g / (2v0^2cos^2THETA) x x^2

## The Attempt at a Solution

i set the details i know at the equation and i got a huge velocity 103.69 m/s
i put it in the equation a=v^2 / r but this is an astronom acceleration
what did i do wrong , i will glad for help and explanation...
thanks!

It would be good to see more details of your calculations. Generally in problems like this, you write one equation for the x motion as a function of time and one for the y motion as a function of time, and solve for the time where the object hits the ground. This let's you get back to the initial velocity, which will give you the centripital acceleration in the circular throwing motion just before release...

i will post mu calculiting :
i talk the Y as the sin21 x 1.3
sin21x1.3= 83 tan21 - ( ( 9.8 x 83^2) /(2Vo^2-cos^2 21)
0.47 = 31.9- ( 67512.2)/(2Vo^2-0.88)
0.94Vo^2= 0.141+(-28072)-67512.2
-62.86Vo^2 = -28.072 - 67512.2
-62.86Vo^2 =-67540.2
V0=103/69 [m/s]
Ar=v^2/r
------------------
i didn't reference to any mass when do i need to refer it ?
thanks

## 1. What is relative motion?

Relative motion is the movement of an object in relation to another object. It takes into account both the object's own movement and the movement of the reference point it is being observed from.

## 2. How is relative motion different from absolute motion?

Absolute motion refers to the movement of an object in relation to a fixed reference point, such as the Earth's surface. Relative motion, on the other hand, considers the movement of an object in relation to another moving object.

## 3. What is the principle of relativity?

The principle of relativity states that the laws of physics are the same for all observers in uniform motion, regardless of their relative velocities. This means that there is no absolute frame of reference for measuring motion and all motion is relative.

## 4. How is relative velocity calculated?

Relative velocity is calculated by subtracting the velocity of the reference point from the velocity of the moving object. This results in the relative velocity, which is the velocity of the object as seen from the reference point.

## 5. What are some real-life examples of relative motion?

Some real-life examples of relative motion include a car moving on a road, a boat sailing on a river, and a person walking on a moving train. In each of these scenarios, the object's movement is affected by the movement of the reference point it is being observed from.

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