Answer:
The fraction of kinetic energy lost in the collision in term of the initial energy is 0.49.
Explanation:
As the final and initial velocities are known it is possible then the kinetic energy is possible to calculate for each instant.
By definition, the kinetic energy is:
k = 0.5*mV^2
Expressing the initial and final kinetic energy for cars A and B:


Since the masses are equals:

For the known velocities, the kinetics energies result:




The lost energy in the collision is the difference between the initial and final kinectic energies:


Finally the relation between the lost and the initial kinetic energy:


Answer:
The value is 
Explanation:
From the question we are told that
The speed of the rope with hook is
The angle is 
The speed at which it hits top of the wall is 
Generally from kinematic equation we have that

Here h is the height of the wall so
![[16.3 sin (65)]^2 = [24.1 sin (65)] ^2+ 2 (-9.8)* h](https://tex.z-dn.net/?f=%5B16.3%20sin%20%2865%29%5D%5E2%20%3D%20%20%5B24.1%20sin%20%2865%29%5D%20%5E2%2B%20%20%202%20%28-9.8%29%2A%20h)
=> 
' +4 m/s² ' means that the pigeon's speed is 4 m/s greater every second.
Starting from zero speed, after 10 seconds, its speed is
(10 x 4m/s) = 40 m/s.
We can't say anything about its velocity, because we have
no information regarding the direction of its flight.
Explanation :
Dispersion forces are also known as London dispersion forces. It is the weakest force. Also, it is the part of the Van der Waals forces.
(1) This force is exhibited by all atoms and molecules.
(2) These forces are the result of the fluctuations in the electron distribution within molecules or atoms. Due to these fluctuations, the electric field is created. The magnitude of this force is explained in terms of Hamaker constant 'A'.
(3) Dispersion forces result from the formation of instantaneous dipoles in a molecule or atom. When electrons are more concentrated in a place, instantaneous dipoles formed.
(4) Dispersion force magnitude depends on the amount of surface area available for interactions. If the area increases, the size of the atom also increase. As a result, stronger dispersion forces.
So, the false statement is "Dispersion forces always have a greater magnitude in molecules with a greater molar mass".