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:
The upper motor neurons synapse in the spinal cord connect with anterior horn cells of lower motor neurons, usually via interneurons. The anterior horn cells are the cell bodies of the lower motor neurons and are located in the grey matter of the spinal cord.
Explanation:
Interneurons are the central nodes of neural circuits, enabling communication between the upper motor neurons, sensory or motor neurons located in the brain and spinal cord and they send signals to lower motor neurons or central nervous system (CNS) in the brain stem and spinal cord . When they get a signal from the upper motor neurons, they send another signal to your muscles to make them contract. They play vital roles in reflexes, neuronal oscillations, and neurogenesis in the adult mammalian brain.
Renshaw cells are among the very first identified interneurons. They are excited by the axon collaterals of the motor neurons. In addition, Renshaw cells make inhibitory connections to several groups of motor neurons.
First overtone of open organ pipe is given as

first overtone of closed organ pipe is given as

now they are in unison so we will have




so end correction of both pipes is e = 1 cm
The kinetic energy of the electron is

where

is the mass of the electron and v its speed. Since we know the value of the kinetic energy,

, we can find the value of the speed v:
Answer:
numbers
Explanation:
Virtually all unimaginable processes can be described as the movement of certain objects. To analyze and predict the nature of the movements that result from the different kinds of interactions, some important concepts such as momentum, force and energy have been invented. If momentum, force, and energy are known and expressed in a quantitative way (that is, by numbers) it is possible to establish rules by which the resulting movements can be predicted.