Where Does the Energy Go When a Ball Becomes Embedded?

[barnacksam]

Ive got this question but i don't know how to answer it.

A steam boiler produces steam at a rate of 0.5 kg.s-1. If the specific latent heat of vaporisation of water is 2.3 MJ kg-1:

(a) What power is consumed to achieve this rate?

cheers

 

[Mech_Engineer]

You have the mass flow rate and the specific energy required, so all you need to do is multiply the mass flow rate by the specific energy to get a result of MJ/s, also known as a megawatt (MW).

[tex]\frac{kg}{s} * \frac{MJ}{kg} = \frac{MJ}{s} = MW[/tex]

 

[barnacksam]

thanks a lot

 

[barnacksam]

Just working through a past paper atm, just need a hand with this one as well ha

A ball bearing, of mass 200 g, is dropped from the top of a 200 m building; it falls to the ground and becomes embedded.

(a) Describe the energy changes which take place.
(5 marks)

(b) What is the increase in internal energy of the ground and the ball bearing at the point of impact?
(5 marks)

(c) Calculate the temperature increase of the ball bearing if it absorbs 70% of this internal energy.
(5 marks)

State all assumptions made.

Take the specific heat capacity of the metal to be 460 J kg-1 K-1.

 

[Mech_Engineer]

Why don't you show your own work at an attempted solution? Pay attention to the forms of energy are being presented in the system...

 

[barnacksam]

Ive gone from GPE to kinetic, then i don't understand what happens when it becomes embedded.
then the b) and c) i just don't have a clue

 

[Mech_Engineer]

"Becomes embedded" is important because it means the ball doesn't bounce- hence all of that energy is conserved in other areas. If the energy isn't used to bounce the ball, where does it go?