The correct answer is - Positive acceleration describes an increase in speed; negative acceleration describes a decrease in speed.
Answer:
m =8.81*10^{-6}grams
time t = 52.8 year
Explanation:
GIVEN DATA:
the half life of the CO-60 is, T_1/2 = 5.27 years = 1.663 e+8 s
activity dN/dt = 1 mCi = 3.7 X 10^7 decay/s
activity , 
= ( 3.7 X 10^7 )(1.663*10^8 ) / ln2
= 8.877*10^{16}
Number of moles:
n = N/NA = 8.877*10^{16} / 6.022X10^23 = 1.474*10^{-7} mol
mass of the CO-60 is,
m = n*M = [1.474*10^{-7} mol]*[59.93 grams /mol] = 8.81*10^{-6}grams
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time t = -[T1/2 / ln2]*ln[N/N0]
= - [5.3 years / ln2]*ln[1x10-6/1x10-3]
= 52.8 year
Answer:
a b c d e f g h I love you will you marry me
Answer:
(a), (c) and (e) s correct.
Explanation:
a. the power used by a circuit is the resistance times the current squared.
The power is given by P = I^2 R, so the statement is correct.
b. electric and magnetic fields are transporting the energy.
false
c. electrons are transporting the energy.
The energy is transferred by flow of electrons. It is correct.
d. the power used by a circuit is the voltage times the current squared.
The power is given by P = V I, the statement is wrong.
e. the power used by a circuit is the current times the voltage.
The power is given by P = V I, the statement is correct.
The answer is : We’ll see the bell move, but we won’t hear it ring. This is because light can travel through vacuum but sound cannot. Sound waves are vibrations of particles in any media, so sound requires a medium to travel, and it cannot travel in a vacuum as there is no particles to vibrate.
