Answer:
10.0 N West
Explanation:
Imagine East is positive and West is negative. Essentially now we have 2 forces pulling opposite each other on the same plane, so we can add them up.
F1=20N
F2=-30N
F1+F2=Net Force
20+(-30)=-10
Therefore the Net Force is 10N West.
Answer:
She should explain that the Sun is made up of gaseous layers that surround an iron core.
Answer:
39.240 W
Explanation:
Let's start by calculating the work done by the engine. We can assume that it is the same work done by the weight of the object to bring it from 40m to the surface: as much energy it takes to bring it up, the same ammount it takes to bring it down. Said work is 
At this point we can simply apply the definition of power, that is 
, to get the power of the engine is 
Answer:
Explanation:
When the positively charged half shell is brought in contact with the electroscope, its needle deflects due to charge present on the shell.
When the negatively charged half shell is brought in contact with the positively charged shell , the positive and negative charge present on each shell neutralises each other .So both the shells lose their charges .The positive half shell also loses all its charges
When we separate the half shells , there will be no deflection in the electroscope because both the shell have already lost their charges and they have become neutral bodies . So they will not be able to produce any deflection in the electroscope.
Answer:
(i) false
(ii) true
(iii) true
(iv) false
Explanation:
(i) The ratio of Cp and Cv is not constant for all the gases. It is because the value of cp and Cv is different for monoatomic, diatomic and polyatomic gases.
So, this is false.
(ii) For monoatomic gas
Cp = 5R/2, Cv = 3R/2
So, thier ratio
Cp / Cv = 5 / 3 = 1.67
This statement is true.
(iii) for diatomic gases
Cp = 7R/2, Cv = 5R/2
Cp / Cv = 7 / 5 = 1.4
This statement is true.
(iv) It is false.
