Answer:
R_cm = 4.66 10⁶ m
Explanation:
The important concept of mass center defined by
R_cm = 1 / M ∑ x_i m_i
where M is the total mass, x_i and m_i are the position and masses of each body
Let's apply this expression to our case.
Let's set a reference frame where the axis points from the center of the Earth to the Moon,
R_cm = 1 / M (m_earth 0 + m_moon d)
the total mass is
M = m_earth + m_moon
the distance from the Earth is zero because all mass can be considered to be at its gravimetric center
let's calculate
M = 5.98 10²⁴ + 7.35 10²²
M = 6.0535 10₂⁴24 kg
we substitute
R_cm = 1 / 6.0535 10²⁴ (0 + 7.35 10²² 3.84 )
R_cm = 4.66 10⁶ m
The sun's source of energy is know as nuclear fusion (means to fuse) this process has a small nuclei atoms that join together to form a large nucleus. The result of this process is released energy. The fusion of hydrogen into helium in the sun makes a large amount of energy and this is known as the sun's energy source.
The theories that scientist proposed about the source of the sun's energy was that the sun burned fuel to generate its energy and that gravity was causing the sun to shrink slowly and have its energy released. Also both of these theories were disproved.
.
Answer:
(A) No
(B) Speed decreases
Explanation:
(A) since there is nothing propelling the boat and the friction between the ice and the boat and also air resistance is negligible the net force of the system in the horizontal direction is zero and hence there is no change in the horizontal momentum of the boat.
(B) Since the person had not velocity in the horizontal direction before landing on the boat but now has one after landing on the boat, the speed of the boat will decrease because the momentum has to be conserved (remember there is no change in it).
Answer:
P = 1097 Watt
Explanation:
given,
length of stairs, L = 130 m
inclination with horizontal,θ = 30°
mass of the football player = 105 Kg
time = 61 s
we know,

Work = change in Potential energy
h = L sin 30°
h = 130 x 0.5
h = 65 m
W = m g h
W = 105 x 9.8 x 65
W = 66885 J
now,

P = 1097 Watt
hence, the power output on the way is 1097 W
Answer:
The electron cloud
Explanation:
Metallic bonds result from interaction of positively charged metal ions with free valence electrons which now forms an electron cloud around the metal ions. Electrostatic interaction between the metal ions and the electron cloud holds the metal ions together in the metallic bond.