Answer:
25.71 kgm/s
Explanation:
Let K₁ and K₂ be the initial and final kinetic energies of object A and v₁ and v₂ its initial and final speeds.
Given that K₂ = 0.7K₁
1/2mv₂² = 0.7(1/2mv₁²)
v₂ = √0.7v₁ = √0.7 × 20 m/s = ±16.73 m/s
Since A rebounds, its velocity = -16.73 m/s and its momentum change, p₂ = mΔv = m(v₂ - v₁) = 0.7 kg (-16.73 - 20) m/s = 0.7( -36.73) = -25.71 kgm/s.
Th magnitude of object A's momentum change is thus 25.71 kgm/s
Answer:
4 x 10⁻⁴ J
Explanation:
C = 5000 pF, V = 400 V
Energy = CV²/2 = 5000 x 10⁻¹² x 400²/2 = 4 x 10⁻⁴ J
The answer is d because you have to make sure that everything is right
Answer:
A super conductor is a perfect conductor that has zero resistance. It doesn't just have very low resistance and conducts electricity well, it has ZERO resistance and conducts electricity perfectly with no losses at all
Gamma rays, X-rays, most ultraviolet rays, and some infrared are absorbed by the atmosphere but do not reach the Earth's surface
