<span> In radioactive decay, an unstable atomic nucleus emits particles or radiation and converts to a different atomic nucleus. If the new nucleus is unstable, it will decay again, until eventually, a stable nucleus is formed. Such a sequence of nuclear decays forms a decay series.
The half-life of a radioactive substance is the time required for half of the atoms of a radioactive isotope to decay. If you have, say, 1 million atoms of a specific isotope in a sample, the time required for 500,000 of those atoms to decay is the half-life of that specific isotope. If you have 50 atoms of that isotope, 25 atoms will decay in the same amount of time.
Because the half-life is fixed for a specific isotope, it can be used to date objects. You compare the decay rate of an old object with the decay rate of a fresh sample. Nuclear decay is a first-order process and can be described by a specific mathematical equation, which depends on the decay rate and the half-life. Knowing those values, you can work back and determine the age of an object, as compared with a standard sample. Old objects will not have as much of a radioactive isotope in them as new objects, since the isotopes will have decayed over time in the old object.</span>
-- The net vertical force on the object is zero.
Otherwise it would be accelerating up or down.
-- The net horizontal force on the object is zero.
Otherwise it would be accelerating horizontally,
that is, its 'velocity' would not be constant. That
would contradict information given in the question.
The total net force on the object is the resultant of the
net vertical component and net horizontal component.
Total net force = √(0² + 0²)
= √(0 + 0)
= √0
= Zero.
The correct answer is the last choice on the list.
Also, you know what ! ? It doesn't even matter whether the surface it's
sliding on is frictionless or not.
If the object's velocity is constant, then the NET force on it must be zero.
If it's sliding on sandpaper, then something must be pushing it with constant
force, to balance the friction force, and make the net force zero. If the total
net force isn't zero, then the object would have to be accelerating ... either
its speed, or its direction, or both, would have to be changing.
The mass of this bag of cement in S.I. units (kg) is equal to 0.062 kilograms.
<u>Given the following data:</u>
- Mass of cement = 62 grams.
To calculate the mass of this bag of cement in S.I. units (kg):
<h3>How to convert to
S.I. units.</h3>
In Science, kilograms (kg) is the standard unit of measurement or S.I. units of the mass of a physical object. Thus, we would convert the value of the mass of this bag of cement in grams to kilograms (kg) as follows:
<u>Conversion:</u>
1000 grams = 1 kilograms.
62 grams = X kilograms.
Cross-multiplying, we have:
X = 
X = 0.062 kilograms.
Read more on mass here: brainly.com/question/13833323
V₀ = V₁ + 2ax
V₀ = final velocity which is 0 m/s
V₁ = initial velocity which is 20 m/s
x = distance which is 60-(0.5 x 20) =50m
this is because his reaction time is 0.5 sec so he traveled 10m before stepping on the break paddle.
a= (V₀-V₁) / 2x
= (0-20) / 2*50
= -0.2m/s
the negative is because it is a deceleration speed hence it is 0.2m/s
Answer:
Every object has a different density and therefore carries different properties. When rays of white light strike an object, each ray light strikes the object with different frequency and therefore is absorbed and reflected differently from the host object.
In case if all the frequencies are absorbed by the object, it turns out to be black in color. Whereas on the other hand, if it is a mix of absorption and reflection, it makes different colors based on its frequencies and other properties of the object.
