Answer:
<em>The rubber band will be stretched 0.02 m.</em>
<em>The work done in stretching is 0.11 J.</em>
Explanation:
Force 1 = 44 N
extension of rubber band = 0.080 m
Force 2 = 11 N
extension = ?
According to Hooke's Law, force applied is proportional to the extension provided elastic limit is not extended.
F = ke
where k = constant of elasticity
e = extension of the material
F = force applied.
For the first case,
44 = 0.080K
K = 44/0.080 = 550 N/m
For the second situation involving the same rubber band
Force = 11 N
e = 550 N/m
11 = 550e
extension e = 11/550 = <em>0.02 m</em>
<em>The work done to stretch the rubber band this far is equal to the potential energy stored within the rubber due to the stretch</em>. This is in line with energy conservation.
potential energy stored = 
==> 
= <em>0.11 J</em>
Answer:
Explanation:
One of the first propulsion characteristics given in the example is that all engines are equal.
In this way if we have 4 engines running at the same time, it means that its capacity is 100%.
Under this premise, if 100% is found, the Jet is capable of reaching a speed of 8.7m / s ^ 2.
However, the question is, what would happen if 2.4 "Engines" now work.
To do this then we make a simple equivalence,
If 4 engines is the equivalent of 100%, when would it be 2.4 engines?
In this way it would mean that the body could be driven to 60% of its total.
So
Answer:
<em>the minimum speed that the ball must have so that the cord does not become slack is</em> <em>2.02 m/s.</em>
<em></em>
Explanation:
In order to avoid slack, the centripetal force of the ball must equal its weight at the top of the circle. Therefore,
F_c = F_g
m v² / r = m g
v² = g r
v = √[g r]
v = √[(9.8 m/s²)(0.417 m)]
<em>v = 2.02 m/s </em>
Therefore,<em> the minimum speed that the ball must have so that the cord does not become slack is</em> <em>2.02 m/s.</em>
Answer:
The part that completes the nuclear equation is:
Explanation:
<h2>A) Preliminar explanation</h2>
The <em>nuclear equation</em> represents a nuclear reaction: the change of the nucleus of an atom.
The given equation represents an actinium atom releasing an alpha particle.
This is the meaning of each part of the equation:
- Ac is the chemical symbol of actinium
- The superscript to the left of the chemical symbol is the mass number of the atom (number of protons plus number of neutrons). The mass number is 225.
- The subscript to the left of the chemical symbol is the atomic number of the atom (number of protons). The atomic number is 89.
is the symbol of the alpha particle. It is an atom of helium- The mass number is 4
- The atomic number is 2
<h2>B) Solution</h2>
To <em>complete the nuclear equation </em>you must do two balances: mass number balance and atomic number balance.
<u>i) Mass number balance</u>
- 225 = A + 4 ⇒ A = 225 - 4 = 221
<u>ii) Atomic number balance</u>
- 89 = Z + 2 ⇒ Z = 89 - 2 = 87
Therefore, the mass number of the unknown atom is 221, and the atomic number is 87.
From a periodic table, the element with atomic number 87 is francium, Fr.
Now, you have the chemical symbol, the atomic number, and the mass number of the unknown atom, which lets you to write the atom that completes the <em>nuclear equation</em>.
