Answer:
The law of inertia
Explanation:
A body at rest will remain at rest, and a body in motion will remain in motion unless it is acted upon by an external force
Answer:

Explanation:
We can use Newton's Universal Law of Gravitation to solve this problem:
., where
is acceleration due to gravity at the planet's surface,
is gravitational constant
,
is the mass of the planet, and
is the radius of the planet.
Since acceleration due to gravity is given as
, our radius should be meters. Therefore, convert
kilometers to meters:
.
Now plugging in our values, we get:
,
Solving for
:
.
We know that the source of light in the universe is the Sun. Hence, the light we see as moonlight travels from the Sun's surface, to the moon, then to Earth. So, before being able to solve this problem, we have to know the distance between the Sun and the moon, and the distance between the moon and Earth. In literature, these values are 3.8×10⁵ km (Sun to moon) and 384,400 km (moon to Earth). Knowing that the speed of light is 300,000 km per second, then the total time would be
Time = distance/speed
Time = (3.8×10⁵ km + 384,400 km)/300,000 km/s
Time = 2.548 seconds
Thus, it only takes 2.548 for the light from the Sun to reach to the Earth as perceived to be what we call moonlight.
Answer:
<h2> 27m/s</h2>
Explanation:
Given data
initital velocity u=15m/s
deceleration a=3m/s^2
time t= 4 seconds
final velocity v= ?
Applying the expression
v=u+at------1
substituting our data into the expression we have
v=15+3*4
v=15+12
v=27m/s
The velocity after 4 seconds is 27m/s
To solve this problem it is necessary to apply an energy balance equation in each of the states to assess what their respective relationship is.
By definition the energy balance is simply given by the change between the two states:

Our states are given by



In this way the energy balance for the states would be given by,



Therefore the states of energy would be
Lowest : 0.9eV
Middle :7.5eV
Highest: 8.4eV