Answer:
D. 130 J
Explanation:
The coefficient of performance for a machine that is being used to cool, is given by:
Here 
is the heat removed from the cold reservoir, W is the work required, that is, the energy required to remove the heat from the interior of the house, 
is the cold temperature and 
is the hot temperature. Recall use absolutes temperatures(
). Replacing and solving for W:
Answer:
Explanation:
Atoms form chemical bonds to make their outer electron shells more stable. ... An ionic bond, where one atom essentially donates an electron to another, forms when one atom becomes stable by losing its outer electrons and the other atoms become stable (usually by filling its valence shell) by gaining the electrons.
Mental and non mental, an ionic bond is a type of chemical bond formed through an electrostatic attraction between two oppositely charged ions. Ionic bonds are formed between a cation, which is usually a metal, and an anion, which is usually a nonmetal.
Answer:E
Explanation:
It is given that Energy of gamma ray is E=1.2 Mev
Shielding effect can be measured by measuring the fraction of gamma rays blocked by shield. If certain thickness will able to block half the radiation then to block 75% radiation we need to add same amount of thickness in order to block the remaining radiation.
i.e. 
fraction is blocked by 10 cm thickness
then remaining radiation is
another 10 cm thickness will block the remaining half radiation i.e. 
so total 75 % radiation will be blocked
Answer:
a set up where current flows without a voltage difference
Explanation:
because a circuit is a set up of different components, and throughout the circuit the voltage is the same, even with more components
