Answer:

Explanation:
According to the law of conservation of linear momentum, the total momentum of both pucks won't be changed regardless of their interaction if no external forces are acting on the system.
Being
and
the masses of pucks a and b respectively, the initial momentum of the system is

Since b is initially at rest

After the collision and being
and
the respective velocities, the total momentum is

Both momentums are equal, thus
Solving for 


The initial kinetic energy can be found as (provided puck b is at rest)


The final kinetic energy is


The change of kinetic energy is

Since there is no friction between the ladder and the wall, there can be no vertical force component. That's the tricky part ;)
So to find the weight, divide the 100N <em>normal</em> force by earths gravitational acceleration, 9.8m/s^2

Then;
Draw an arrow at the base of the ladder pointing towards the wall with a value of 30N, to show the frictional force.
Answer:
A nuclear winter is a climatic phenomenon that would follow the detonation of several atomic bombs in the event that a nuclear war broke out. These bombs would cause firestorms that would raise smoke, dust and particles into the atmosphere that would end up in the stratosphere and eventually spread throughout the globe.
Explanation:
That idea is far fetched, because even though those same particles would absorb sunlight, it would raise the temperature in the stratosphere and cause a decrease in temperature in the Earth's layer. Unable to seep the sun's rays, many plant species would die and this would affect the entire food chain.
In addition, that temperature rise in the stratosphere would destroy part of the ozone layer, causing greater exposure to ultraviolet rays. This would end up affecting health and further damaging plant species.
A. Illustrates how a theory becomes a law
Answer:
For two waves of equal amplitude interfering constructively, the resulting amplitude is twice as large as the amplitude of an individual wave. For 100 waves of the same amplitude interfering constructively, the resulting amplitude is 100 times larger than the amplitude of an individual wave.