Answer:
A. the internal energy stays the same
Explanation:
From the first law of thermodynamics, "energy can neither be created nor destroyed but can be transformed from one form to another.
Based on this first law of thermodynamic, the new internal energy of the gas is the same as the internal energy of the original system.
Therefore, when the partition separating the two halves of the box is removed and the system reaches equilibrium again, the internal energy stays the same.
Answer:
(a)
(b) Kinetic Energy of planet with mass m₁, is KE₁ = 1.068×10³² J
Kinetic Energy of planet with mass m₂, KE₂ = 2.6696×10³¹ J
Explanation:
Here we have when their distance is d apart
Energy is given by
Conservation of linear momentum gives
m₁·v₁ = m₂·v₂
From which
v₂ = m₁·v₁/m₂
At equilibrium, we have;
which gives
multiplying both sides by m₂/m₁, we have
Such that v₁ =
Similarly, with v₁ = m₂·v₂/m₁, we have
From which we have;
and
The relative velocity = v₁ + v₂ =
v₁ + v₂ =
(b) The kinetic energy KE =
Just before they collide, d = r₁ + r₂ = 3×10⁶+5×10⁶ = 8×10⁶ m
= 10333.696 m/s
=2583.424 m/s
KE₁ = 0.5×2.0×10²⁴× 10333.696² = 1.068×10³² J
KE₂ = 0.5×8.0×10²⁴× 2583.424² = 2.6696×10³¹ J.
Answer:
a = 1.764m/s^2
Explanation:
By Newton's second law, the net force is F = ma.
The equation for friction is F(k) = F(n) * μ.
In this case, the normal force is simply F(n) = mg due to no other external forces being specified
F(n) = mg = 15kg * 9.8 m/s^2 = 147N.
F(k) = F(n) * μ = 147N * 0.18 = 26.46N.
Assuming the object is on a horizontal surface, the force due to gravity and the normal force will cancel each other out, leaving our net force as only the frictional one.
Thus, F(net) = F(k) = ma
26.46N = 15kg * a
a = 1.764m/s^2