# Kinetic energy of hail stone

• dobbygenius
In summary, it is likely that hailstones would melt upon impact with the Earth's surface due to their high velocity of 824 m/s. However, this is also dependent on the size and composition of the hailstones as well as the surface they are hitting. The majority of the kinetic energy would be absorbed by the ice, making it more likely for the hailstones to melt.f

#### dobbygenius

Homework Statement
by reference to your answer in part (a), suggest whether hailstones are likely to melt on hitting the Earth's surface
Relevant Equations
mL=1/2mv^2

I'm pretty sure the hailstones are likely to melt/disperse because 824 m/s is a high velocity but can someone help me elaborate why it would melt?

Delta2
Homework Statement:: by reference to your answer in part (a), suggest whether hailstones are likely to melt on hitting the Earth's surface
Relevant Equations:: mL=1/2mv^2

I'm pretty sure the hailstones are likely to melt/disperse because 824 m/s is a high velocity but can someone help me elaborate why it would melt?
Do you mean to say the hailstones would melt? Or wouldn't melt?

PS I'm not sure why all the KE would transform to heat in the hailstone. Why wouldn't about half the energy go to heat in the ground at the point of impact?

Do you mean to say the hailstones would melt? Or wouldn't melt?
yes, the hailstones would melt...but I don't know how to elaborate on that

PS I'm not sure why all the KE would transform to heat in the hailstone. Why wouldn't about half the energy go to heat in the ground at the point of impact?
You're right I just followed what the question said

yes, the hailstones would melt...but I don't know how to elaborate on that
With what speed do hailstones hit the Earth?

With what speed do hailstones hit the Earth?
the first question asked to find the minimum speed for it to melt when it hits the surface and I found it to be 824 m/s but other than that both the first and second question didn't give any more data

the first question asked to find the minimum speed for it to melt when it hits the surface and I found it to be 824 m/s but other than that both the first and second question didn't give any more data
Do you think hailstones hit the ground at ##824 \ m/s## or more? Have you ever seen hailstones?

I'm pretty sure the hailstones are likely to melt/disperse because 824 m/s is a high velocity but can someone help me elaborate why it would melt?
Your reasoning is backwards. If it requires a very high velocity to melt the hailstones then that makes it relatively unlikely that hailstones would melt in practice.
So the question is, is such a high impact speed likely?
PS I'm not sure why all the KE would transform to heat in the hailstone. Why wouldn't about half the energy go to heat in the ground at the point of impact?
Because most of the inelastic deformation would be in the ice.

Because most of the inelastic deformation would be in the ice.
That's a subtle assumption. It depends what the hailstones hit. Large hailstones may damage a car roof, for example, causing inelastic deformation of the metal.

Do you think hailstones hit the ground at ##824 \ m/s## or more? Have you ever seen hailstones?
No, I just looked it up, should've done it earlier

PeroK
Your reasoning is backwards. If it requires a very high velocity to melt the hailstones then that makes it relatively unlikely that hailstones would melt in practice.
So the question is, is such a high impact speed likely?

Because most of the inelastic deformation would be in the ice.
Right...thankyou!

That would be a very noisy hailstorm! Lots and lots of little sonic booms

dobbygenius