Answer: When enough __energy__ is added to the substance, the solid reaches its _melting_ point and becomes a liquid
Explanation: since energy is being added the substance changes phase into a liquid .
We have that the momentum p is given by the formula p=mv where m is the mass and v is the velocity. Since for A p=-14kgm/s and m=7, we have that the velocity is -14/7=-2m/s. Hence its speed is 2 m/s.
For b we have that p=15kgm/s and v=3m/s. Because m=p/v, we have m=3kg.
We also have that the momentum is conserved in this system. Hence, the net sum of the momentum of the 2 snowballs equals the momentum of the single giant ball. Hence, p(total)=p(combined)=-14+15=1kgm/s (momentum is a vector; the positive sign means that it tends to the positive direction).
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
