Author Question: A layer of insulating material with thermal conductivity K is placed on a layer of another material ... (Read 214 times)

lidoalex

  • Hero Member
  • *****
  • Posts: 538
A layer of insulating material with thermal conductivity K is placed on a layer of another material of thermal conductivity 2K. The layers have equal thickness. What is the effective thermal conductivity of the composite sheet?
 
  A) 1.5K
  B) 3K
  C) K/3
  D) 2K/3
  E) K/5

Question 2

The radioactive isotope 226Ra (atomic number 88 ) decays to the isotope 222Rn (atomic number 86). What type of radioactive decay is this?
 
  A) beta decay
  B) electron ionization
  C) electron capture
  D) alpha decay



jamesnevil303

  • Sr. Member
  • ****
  • Posts: 337
Answer to Question 1

D

Answer to Question 2

D



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.

Did you know?

To maintain good kidney function, you should drink at least 3 quarts of water daily. Water dilutes urine and helps prevent concentrations of salts and minerals that can lead to kidney stone formation. Chronic dehydration is a major contributor to the development of kidney stones.

Did you know?

The average person is easily confused by the terms pharmaceutics and pharmacology, thinking they are one and the same. Whereas pharmaceutics is the science of preparing and dispensing drugs (otherwise known as the science of pharmacy), pharmacology is the study of medications.

Did you know?

There are more nerve cells in one human brain than there are stars in the Milky Way.

Did you know?

Children of people with alcoholism are more inclined to drink alcohol or use hard drugs. In fact, they are 400 times more likely to use hard drugs than those who do not have a family history of alcohol addiction.

For a complete list of videos, visit our video library