Answer:
an astronomer studies planets, stars, moons, etc, or objects that are outside the field of Earth.
Answer:
so maximum velocity for walk on the surface of europa is 0.950999 m/s
Explanation:
Given data
legs of length r = 0.68 m
diameter = 3100 km
mass = 4.8×10^22 kg
to find out
maximum velocity for walk on the surface of europa
solution
first we calculate radius that is
radius = d/2 = 3100 /2 = 1550 km
radius = 1550 × 10³ m
so we calculate no maximum velocity that is
max velocity = √(gr) ...............1
here r is length of leg
we know g = GM/r² from universal gravitational law
so G we know 6.67 ×
N-m²/kg²
g = 6.67 ×
( 4.8×10^22 ) / ( 1550 × 10³ )
g = 1.33 m/s²
now
we put all value in equation 1
max velocity = √(1.33 × 0.68)
max velocity = 0.950999 m/s
so maximum velocity for walk on the surface of europa is 0.950999 m/s
Answer:

Explanation:
The law of conservation of angular momentum states that angular momentum remains constant when there is no external moment or forces applied to the system. Let assume that star can be modelled as an sphere, then:

The final angular speed is:



Aluminum has an atomic number of 13, so it has 13 protons. In its natural state, it does not have a charge, so it has an equal amount of electrons, 13. The atomic mass of aluminum is approximately 27. Since protons and neutrons make up that mass, and each of the particles are around 1 atomic mass unit, if there are 13 protons, then there are 27-13 neutrons, or 14 neutrons. So the first answer choice is correct.
Answer:
A reference frame is that frame to which the qualities of an object are related:
For instance - an object may described by - mass, speed, acceleration, size, etc,
It is important to remember that Newton's Laws of motion do not hold in accelerated reference frames -
Einstein's laws of special relativity are only true in frames that move with contant speed to one another