Physics lenses/critical angle question need help ASAP
1 answer:
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Answer:
Height, h = 16.67 m
Explanation:
We have,
Mass of a squirrel is 0.765 kg.
He jumps off the tree and hits the ground with 125 joules of energy.
It is required to find the height up on the tree the squirrel was when it jumped.
The energy possessed by the squirrel is called its gravitational potential energy. It can be given by :
h is height up on the tree the squirrel was when it jumped
So, the squirrel will go to a height of 16.67 m.
Answer:
he mass of the emitted particles is small, it is slightly less than the initial 50 kg, so the correct answer is the first.
Explanation:
A radioactive material is transformed into another material by the emission of some particular radioactive ones, the most common being alpha and beta rays, which is why in the transformation process a certain amount of mass is lost. The process is described by the expression
N = No
From this expression the quantity half life time () is defined with time so that half of the atoms have been transformed
T_{1/2} = ln 2 /λ
in this case it does not indicate that T_{1/2}= 20 days is worth, for which periods have passed, in the first the number of radioactive atoms was reduced to half the number, leaving N´ and the second halved the number of nuclei that they were radioactive, leaving radioactive nuclei
first time of life
N´ = ½ N
second time of life
N´´ = ½ N´
N´´ = ¼ N
consequently in the sample at the end of these two decay periods we have, assuming that after each emission the atom is stable (non-radioactive). After the first emission there are n₁ = N / 2 stable atoms, after the second emission n₂ = ¼ N stable atoms are added and there are still n₃ = ¼ N radioactive atoms, so the total number of atoms is
n_total = n₁ + n₂ + n₃
Recall that the mass of the initial radioactive atoms is m₁, when transforming its mass of stable atoms is m₂ where
m₂ < m₁
therefore mass of
m_total = m₂ N / 2 + m₂ N / 4 + m₁ N / 4
m_total = m₂ ¾ N + m₁ ¼ N
m_total = N ( ¾ m₂ + ¼ m₁)
Since the mass of the emitted particles is small, it is slightly less than the initial 50 kg, so the correct answer is the first.