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
Increase in sea water pollution
Answer:
Mechanical waves require a medium in order to transport their energy from one location to another.
Sound waves are incapable of traveling through a vacuum. Slinky waves, water waves, stadium waves, and jump rope waves are other examples of mechanical waves; each requires some medium in order to exist.
Angular frequency in radian per second for 20 vibrations in 10 seconds is 12.6 rad/s
<h3>What is Angular frequency?</h3>
Angular frequency is the number of vibrations in radian per second.
The total number of vibrations n is 20 and the time taken for these vibrations is 10 s
The frequency of the vibrations will be
f = 20 / 10 = 2 Hz
Angular frequency is related to the frequency as
ω = 2πf
ω=2π × 2
ω = 12.6 rad/s
Thus, the angular frequency is 12.6 rad/s.
Learn more about Angular frequency.
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