Answer: D.
Explanation: Just took the quiz.
Answer:
high density can withstand high acceleration and applied forces
Heavy metals are toxic to humans,
the clay is quite abundant and in general it is not toxic
Explanation:
The selection of materials for the construction of rockets takes into account many aspects, the technical resistance to the demands of space travel, but also the abundance of the material. Heavy metals have two very serious problems. The first one, some of them are a little scarce in nature, but the most serious problem is that almost all of them are toxic to humans, for example: lead and mercury.
On the other hand, the clay is quite abundant and in general it is not toxic to living beings.
If we use Newton's second law
F = m a
let's use the concept of density
rho = m / V
m = rho V
let's substitute
F = rho V a
From this expression we see that a material with high density can withstand high acceleration and applied forces, such as those existing in spacecraft clearance and re-entry to Earth.
Unfortunately with this law there is no criterion to select a material unless its density is high, in addition to this criterion low toxicity criteria for human beings are used,
Answer: The correct answer is "the speed of the wave becomes four times".
Explanation:
The relation between the speed, frequency and the wavelength is as follows:
v=f\lambda
Here, v is the speed of the wave, f is the frequency and \lambda is the wavelength.
The speed of the sound wave is directly proportional to the frequency.
In the given problem, if the speed of the sound wave is increased four times then the speed of the sound becomes four times.
Therefore, the speed of the sound wave becomes four times.
Answer:
52 rad
Explanation:
Using
Ф = ω't +1/2αt²................... Equation 1
Where Ф = angular displacement of the object, t = time, ω' = initial angular velocity, α = angular acceleration.
Since the object states from rest, ω' = 0 rad/s.
Therefore,
Ф = 1/2αt²................ Equation 2
make α the subject of the equation
α = 2Ф/t².................. Equation 3
Given: Ф = 13 rad, t = 2.5 s
Substitute into equation 3
α = 2(13)/2.5²
α = 26/2.5
α = 4.16 rad/s².
using equation 2,
Ф = 1/2αt²
Given: t = 5 s, α = 4.16 rad/s²
Substitute into equation 2
Ф = 1/2(4.16)(5²)
Ф = 52 rad.
a. all systems work together to stabilize the body
