Answer:
the period of the 16 m pendulum is twice the period of the 4 m pendulum
Explanation:
Recall that the period (T) of a pendulum of length (L) is defined as:
where "g" is the local acceleration of gravity.
SInce both pendulums are at the same place, "g" is the same for both, and when we compare the two periods, we get:
therefore the period of the 16 m pendulum is twice the period of the 4 m pendulum.
A)
The total energy of the system is equal to the maximum elastic potential energy, that is achieved when the displacement is equal to the amplitude (x=A):
(1)
where k is the spring constant.
The total energy, which is conserved, at any other point of the motion is the sum of elastic potential energy and kinetic energy:
(2)
where x is the displacement, m the mass, and v the speed.
We want to know the displacement x at which the elastic potential energy is 1/3 of the kinetic energy:
Using (2) we can rewrite this as
And using (1), we find
Substituting into the last equation, we find the value of x:
B)
In this case, the kinetic energy is 1/10 of the total energy:
Since we have
we can write
And so we find:
No, aluminum has a density near 2.7 g/cm^3
<span>7.8 g/cm^3 is near the density of iron (or in the case of a fork, steel).
this is it
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Answer:
a) I = 464 kg m², b) K = 631 .6 J, c) v = 8.25 m / s
Explanation:
a) the moment of inertia of point particles is
I = ∑ m_i r_i²
in this case
I = 8 5² + 3 (-2) ² + 7 (-6) ²
I = 464 kg m²
b) The kinetic energy is
K = ½ I w²
K = ½ 464 1.65²
K = 631 .6 J
c) linear and angular velocity are related
v = w r
v = 1.65 5
v = 8.25 m / s