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Subject to the usual rules about differentiability you can do this with any three related variables.
Yes, it forgot it had a wireless card.
thanks, they are really helpful
If the width decreases linearly then the volume will decrease by the cube of the value of 'm'
Does that help ?
This is what I've got so far.
We want t when x = 0
3) is bothering me. From iit I gather that (V+dV)/V is equal to 1/39.5 in which case the block of ice is melting very rapidly.
I do not understand what the 3rd piece of information is.
Only differentiation. eeekkkk!
hence work out dV/dx using differentiation.
You can also write an expression for the surface area in terms of x and hence write the rate of change of volume
You should be able to work out both numbers.
Stick a minus on this as the volume is decreasing.
As x squared occurs in both of these you can get
This will integrate to an expression like this
m will be negative. Note x will be the vertical axis and t across.
Use the initial volume and volume after one unit ot time to determine this gradient m.
When does the line cut x = 0 ?
That's my best shot I'm afraid. Maybe someone else on the forum will come in with a better suggestion.
i can only use differentiation in this assignment!! So hard:mad:
Cannot be for all time intervals or the amount of melting gets less and less and takes an infinite amount of time. ?????