Answer:
A. Splitting water into hydrogen and oxygen.
Explanation:
A chemical change produces a new substance. ... A physical change does not produce a new substance. Changes in state or phase (melting, freezing, vaporization, condensation, sublimation) are physical changes.
Answer:
Drilling into the seafloor off Mexico, scientists have extracted a unique geologic record of the single worst day in the history of life on Earth, when a city-sized asteroid smashed into the planet 65 million years ago, wiping out the dinosaurs and three-quarters of all other life.
Their analysis of these new rock samples from the Chicxulub crater, made public Monday, reveals a parfait of debris deposited in layers almost minute-by-minute at the heart of the impact during the first day of a global catastrophe. It records traces of the explosive melting, massive earthquakes, tsunamis, landslides and wildfires as the immense asteroid blasted a hole 100 miles wide and 12 miles deep, the scientists said.
Answer:
The final velocity of the car A is -1.053 m/s.
Explanation:
For an elastic collision both the kinetic energy and the momentum of the system are conserved.
Let us call
= mass of car A;
= the initial velocity of car A;
= the final velocity of car A;
and
= mass of car B;
= the initial velocity of car B;
= the final velocity of car B.
Then, the law of conservation of momentum demands that

And the conservation of kinetic energy says that

These two equations are solved for final velocities
and
to give


by putting in the numerical values of the variables we get


and


Thus, the final velocity of the car A is -1.053 m/s and of car B is 3.49 m/s.
Because the direction of the kicks are opposite, the net force between the applied forces is their difference.
Fn = F₂ - F₁
Substituting,
Fn = 15 N - 5 N
Fn = 10 N
From Newton's second law of motion,
Fn = m x a
where m is mass and a is acceleration. Manipulating the equation so that we are able to calculate for a,
a = Fn / m
Substituting,
a = (10 N) / 2 kg
a = 5 m/s²
<em>ANSWER: 5 m/s²</em>