Melting a snowball by throwing it at a wall

[AbsoluteZer0]

Homework Statement

You throw a snowball at 0.0 Celsius at a brick wall. If you want it to melt completely, how fast will you have to throw it?

Homework Equations

[itex] Q = mL [/itex]

[itex] E_k = \frac{1}{2} mv^2 [/itex]

The Attempt at a Solution

I initially reasoned that you would use Q = mL to find the energy needed to melt it and then substitute that into the Kinetic energy formula, giving:

[itex] mL = \frac{1}{2} mv^2 [/itex]

However, I am given no information regarding the mass of the snowball and haven't figured out a method to find that mass.
Any suggestions?

Thanks,

 

[Saitama]

Why do you need mass when it cancels out in the equation you formed?

 

[trollcast]

Homework Statement

You throw a snowball at 0.0 Celsius at a brick wall. If you want it to melt completely, how fast will you have to throw it?

Homework Equations

[itex] Q = mL [/itex]

[itex] E_k = \frac{1}{2} mv^2 [/itex]

The Attempt at a Solution

I initially reasoned that you would use Q = mL to find the energy needed to melt it and then substitute that into the Kinetic energy formula, giving:

[itex] mL = \frac{1}{2} mv^2 [/itex]

However, I am given no information regarding the mass of the snowball and haven't figured out a method to find that mass.
Any suggestions?

Thanks,

Just assume that mass equals 1.

 

[AbsoluteZer0]

Why do you need mass when it cancels out in the equation you formed?

Ah!
I didn't notice that. Thanks.

I'm now at

[itex]L = \frac{1}{2}v^2 [/itex]

Edit:

I changed 334 j/g to 334000 j/kg and arrived at around 800 m/s

 

[haruspex]

If you want your working checked, please post it.