Answer:
a)
b)
c) ΔK=
d)ΔK=
Explanation:
From the exercise we know that there is a collision of a sports car and a truck.
So, the sport car is going to be our object number 1 and the truck object number 2.
Since the two vehicles remain locked together after the collision the final mass is:
a) To find the velocity of the two vehicles just after the collision we must use linear's momentum principle
b) To find the speed the truck should have had so both vehicles stopped in the collision we need to use the same principle used before
c) To find the change in kinetic energy we need to do the following steps:
ΔK=
ΔK=
d) The change in kinetic energy where the two vehicles stopped in the collision is:
ΔK=
ΔK=
The following formula gives the connection between the force, the mass and the acceleration:
F=ma
In our case we know the force and the mass. F=20N and m=10kg
a=F/m
a=20m/s^2/10=2<span>m/s^2</span>
The Pony Express
Chapter 1
At A Nation's Crisis
The Pony Express was the first rapid transit and the first fost mail line across the continent from the Missouri River to the Pacific Coast. It was a system
by means of which messages were carried swiftly on horseback across the plains and deserts, and over the mountains of the far West It brought the
Adontic coost and the Pacific slope ten days nearer to each other.
It had a brief existence of only sixteen months and was supplanted by the transcontinental telegraph. Yet it was of the greatest importance in
binding the East and West together at a time when overland travel was slow and cumbersome, and when a great national crisis made the rapid
communication of news between these sections an imperative necessity.
The Pony Express marked the highest development in overland travel prior to the coming of the Pacific railroad, which it preceded nine years.
It, in fact, proved the feasibility of a transcontinental road and demonstrated that such a line could be built and operated continuously the year
around-a feat that had always been regarded as impossible.
The operation of the Pony Express was a supreme achievement of physical endurance on the part of man and his ever faithful companion, the
horse. The history of this organization should be a lasting monument to the physical sacrifice of man and beast in an effort to accomplish
something worthwhile. Its history should be an enduring tribute to American courage and American organizing genius.
Read this line from the Pony Express excerpt
It hod a brief existence of only sixteen months and was supplanted by the transcontinental telegraph.
Based on the corres, what does the word "supplanted" mean? (5 points)
Defeated
Joined
Replaced
Os
Oo
Unearthed
The capacitor is used to store electric charge.That is what makes capacitors special. <span>
The charge that flows into the capacitor is stored on the plate of the capacitor that the source voltage is connected to. </span>When current flows into a capacitor, the charges get “stuck” on the plates because they can’t get past the insulating dielectric. One plate is positively charged and the other negatively <span>The stationary charges on these plates create an </span>electric field. <span>When charges group together on a capacitor like this, the cap is storing electric energy just as a battery might store chemical energy.</span>