# Curling Physics

1. Feb 26, 2009

### Soulsteppa90

1. The problem statement, all variables and given/known data
Two curling contestants dispute possession of a stone of mass 20.6 kg. The mass of contestant A is 58.9 kg, whereas that of contestant B is 101.7 kg. Contestant A pulls on the stone with a horizontal force of 15.1 N, but is unable to break contestant B’s grip. The result is a stalemate (the stone does not accelerate).

a) Neglecting (for now) frictional forces between the stone and the ice, what is the horizontal force that contestant B exerts on the stone? [Note: Indicate a pull (a force in contestant B’s direction) by a positive sign and a push (a force in contestant A’s direction) by a negative sign.]

b) What is the minimum coefficient of static friction required between the contestants and the ice (assume that it is the same for both contestants)?

2. Relevant equations
F=ma

3. The attempt at a solution
I do not even know where to start

2. Feb 26, 2009

### Delphi51

Diagram!
Show the forces acting on the curling rock.
Note that it does not accelerate.

3. Feb 26, 2009

### Soulsteppa90

I'm still a little confused on how to solve this. Can you please elaborate on how to solve this problem.

4. Feb 26, 2009

### Delphi51

<--- rock ---->
The size of the forces was given - put them on the diagram.
Write that the sum of the forces equals ma

5. Mar 5, 2009

### elcaptain

worst.help.ever.

6. Mar 6, 2009

### Redbelly98

Staff Emeritus
And, appropriately so. Other than writing "F=ma" the OP has not demonstrated any real effort, as is required to receive help here.

7. Mar 15, 2010

### Newton=boss

I have the same question, and the relevant equations for the section are Energy equations and possibly momentum equations.

K=.5mv^2=Fd

m1v1=m2v2

however, like the OP, as the stone is at rest and has zero net acceleration/ force I do not know which equation to even use. If anyone caould point us in the right direction, I would be quite appreciative as well

8. Mar 15, 2010

### Newton=boss

oh and F frictional=mu*Normal Force

9. Mar 15, 2010

### Redbelly98

Staff Emeritus
Start with part (a), and list all the forces that are acting on the stone. As you noted, the net force on the stone must be zero.

10. Mar 16, 2010

### Newton=boss

Its deceptively simple!