Answer:
A half-life is the time required for one half of the nuclei in a radio- active isotope to decay.
Explanation:
A radio-active isotope is an isotope which undergoes radioactive decay.
Radioactive decay is a spontaneous process in which the nucleus of an atom changes its state (turning into a different nucleus, or de-exciting), emitting radiation, which can be of three different types: alpha, beta or gamma.
The half-life of a radio-active isotope is the time required for half of the nuclei of the initial sample to decay.
The law of radio-active decay can be expressed as follows:

where
N(t) is the number of undecayed nuclei left at time t
N0 is the initial number of nuclei
t is the time
is the half-life
We see that when
(that means, when 1 half-life has passed), the number of undecayed nuclei left is

So, half of the initial nuclei.
Since the y axis stayed consistent, we can assume it did not move at all.
(So your answer would be A)
<h2>The voltmeter reading will be 35.7 volt </h2>
Explanation:
The resistor 1000 ohm and 4000 ohm are connected in parallel .
Their combined resistance is supposed R₁
Thus
=
+
or R₁ = 800 ohm
Therefore the total resistance in circuit is = 2000 + 800 = 2800 ohm
Because these are in series .
We can find current flowing through the circuit I =
=
= 
here R is total resistance .
The potential difference across 1000 ohm =
x 1000 = 35.7 volt
Thus voltmeter reading will be 35.7 volt
Answer:
conservation of momentum, general law of physics according to which the quantity called momentum that characterizes motion never changes in an isolated collection of objects; that is, the to