I need help with 2 questions that I cant seem to figure out. I had them for homework but I never got it right and the homework has since been turned in.(adsbygoogle = window.adsbygoogle || []).push({});

I was told I would most likely see these problems again on the exam. Therefore I need to learn how to do them. Can anyone help me out on these?

Question 1:

A certain strom cloud has a potential difference of 8.9 x 10^7 V relative to a tree. Water has a specific heat of 4186 J/kg*C, a boiling point of 100 Celsius and a heat of vaporization of 2.26 x 10^6 J/kg.

If, during a lightning storm, 52 C charge is transferred through this potential difference and 1.96% of the netery is absorbed by the tree, how much water (sap in the tree) initially at 20.9 Celcius can be boiled away? Answer in kg.

Question 2:

An insulating sphere of radius 14 cm has a uniform charge dnesity through its volume. If the magnitude of the electric field at a distance of 7.5029 cm from the center is 98545.6 N/C, what is the magnitude of the electric field at 28.0078 cm from the center? Answer in N/C. (Radius of sphere is 14 cm)

If anyone can help me I would really appreciate it.

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# Homework Help: Help needed with 2 physics questions

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