Density = Mass / Volume
Mass = Density * Volume
Mass = 30 g/cm³ * 10 cm³ = 300 g
Mass = 300 g
Indirect evidence must be used to study the structure of atoms, because the direct evidence affects the position and energy of the particles of the atomic structure.
For example, imagine you use a light ray to find the location of an electron in an atomic structure, the current location of the electron you are now seeing is as a result of the light ray, and the electron has changed it's initial position to a new position as a result of the effect of the light ray.
So indirect means would probably give more accurate answers about the atomic structure than that of the direct means.
An example of the indirect means would be for example setting up a mathematical equation or model of the atomic structure and trying to provide solution for the model or equation.
Answers:
a) 30 m/s
b) 480 N
Explanation:
The rest of the question is written below:
a. What is the final speed of the falcon and pigeon?
b. What is the average force on the pigeon during the impact?
<h3>a) Final speed</h3>
This part can be solved by the Conservation of linear momentum principle, which establishes the initial momentum
before the collision must be equal to the final momentum
after the collision:
(1)
Being:


Where:
the mas of the peregrine falcon
the initial speed of the falcon
is the mass of the pigeon
the initial speed of the pigeon (at rest)
the final speed of the system falcon-pigeon
Then:
(2)
Finding
:
(3)
(4)
(5) This is the final speed
<h3>b) Force on the pigeon</h3>
In this part we will use the following equation:
(6)
Where:
is the force exerted on the pigeon
is the time
is the pigeon's change in momentum
Then:
(7)
(8) Since 
Substituting (8) in (6):
(9)
(10)
Finally:

Answer:
A) a = 73.304 rad/s²
B) Δθ = 3665.2 rad
Explanation:
A) From Newton's first equation of motion, we can say that;
a = (ω - ω_o)/t. We are given that the centrifuge spins at a maximum rate of 7000rpm.
Let's convert to rad/s = 7000 × 2π/60 = 733.04 rad/s
Thus change in angular velocity = (ω - ω_o) = 733.04 - 0 = 733.04 rad/s
We are given; t = 10 s
Thus;
a = 733.04/10
a = 73.304 rad/s²
B) From Newton's third equation of motion, we can say that;
ω² = ω_o² + 2aΔθ
Where Δθ is angular displacement
Making Δθ the subject;
Δθ = (ω² - ω_o²)/2a
At this point, ω = 0 rad/s while ω_o = 733.04 rad/s
Thus;
Δθ = (0² - 733.04²)/(2 × 73.304)
Δθ = -537347.6416/146.608
Δθ = - 3665.2 rad
We will take the absolute value.
Thus, Δθ = 3665.2 rad
Answer:
v = 1 m/s
Explanation:
from the principle of conservation of momentum, we have following relation
initial momentum = final momentum

where
m1 = 1.14 kg
v1 = 2.0 m/s
m2 = 1.14 kg
v2 = 0 m/s
putting all value in the above equation


v = 1 m/s