Answer:

Explanation:
consider the mass of each train car be m
m₁ = m₂ = m₃ = m
speed of the three identical train
u₁ = u₂ = u₃ = 1.8 m/s
m₄ = m u₄ = 4.5 m/s
m₅ = m u₅ = 0 (initial velocity )
final velocity
v₁ = v₂ = v₃ = v₄ = v₅ = v
using conservation of momentum
m₁u₁ + m₂u₂ + m₃u₃ + m₄u₄ + m₅u₅ = m₁v₁ + m₂v₂ + m₃v₃ + m₄v₄ + m₅v₅
m (1.8 + 1.8 + 1.8 +4.5) = 5 m v


Answer:
Differences
microscopic refers to substances visible to the naked eye
macroscopic are substances invisible to naked eye
Similarities
both refer to different scales that are useful to determining the size to different compounds.
Explanation:
Ima find more
Answer:
Sound waves are pushed closer together, decreasing wavelength
and increasing frequency.
Answer:
True
Explanation:
In an alternating current, voltage levels can be easily increased or decreased as per the requirements of the energy distribution in practical world.
Hence, the given statement is true
Answer:
Three different types of levers exist, depending on where the input force, fulcrum, and load are. A class 1 lever has the fulcrum between the input force and load. A class 2 lever has the load between the fulcrum and input force. A class 3 lever is a lever that has the input force in between the fulcrum and the load.
Explanation: