A student is sitting in a chair with nearly frictionless rollers. Her homework bag is in an identical chair right beside her. The chair and the bag havera combined mass of 20 kg. The
student and her chair have a combined mass of 65 kg. If she pushes her homework bag away
from her at 0.060 m/s relative to the floor, what will be the student's velocity immediately
after the interaction ? (Show your work)

-0.018 m/s

Explanation:

Momentum is conserved.

m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂

Both masses start at rest, so u₁ = u₂ = 0 m/s.

0 = m₁v₁ + m₂v₂

0 = (20 kg) (0.060 m/s) + (65 kg) v₂

v₂ ≈ -0.018 m/s

co2reflects heat radiation back to earth buning coal and oil emits co2 globe warms

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

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