Answer:
B. A well-tested explanation for a widely accepted hypothesis
Explanation:
This is true about a scientific theory going by the fact of it being a well tested explanation. For example, in one of the Newtons law of motion which he stated to be<em> "To every action, there is equal and opposite reaction", </em><em>the hypothesis has been known till he was able to offer a well tested explanations with calculations showing that, it was actually true.</em>
Answer:
B. 3
Explanation:
The half-life of a radioisotope is the time it needs for the mass of the radioisotope to halve with respect to its original value.
In this problem, the initial mass of the radioisotope at t=0 is
m0 = 50.0 mg
We see that after t = 1 min, the mass of the isotope is
m(1 min) = 25.0 mg
so, exactly half the initial mass: this means that 1 minute is exactly the half-life of this radioisotope.
So, the amount of mass left after each minute is the following:
m (1 min ) = 25.0 mg (1 half-life)
m (2 min) = 12.5 mg (2 half-lives)
m (3 min) = 6.25 mg (3 half-lives)
so, when we are left with 6.25 mg of isotope, 3 minutes have passed, which means that 3 half-lives have passed.
Answer:
B. Two waves have displaced in opposite directions
Explanation:
Interference occurs when two waves meet at a point in space. When this occurs, two extreme conditions can occur:
- if the two waves are in phase (=displacement in the same direction), the amplitude of the resultant wave is equal to the sum of the amplitudes of the two waves:
A = A1 + A2
and this condition is called constructive interference
- if the two waves are in anti-phase (=displacement in opposite directions), the amplitude of the resultant wave is equal to the difference of the amplitudes of the two waves:
A = |A1 - A2|
and this condition is called destructive interference. Note that if A1=A2, the amplitude of the resultant wave is zero.
Between magnitude of the average 4sec
Answer:
It is called an ion.
Explanation:
Atoms of elements can lose or gain electrons making them no longer neutral, they become charged. A charged atom is called an ion. When an atom loses electron(s) it will lose some of its negative charge and so becomes positively charged. A positive ion is formed where an atom has more protons than electrons.