Basic is the answer. (i think so)
Let the mass of 2500 kg car be
and it's velocity be
and the mass of 1500 kg car be
and it's velocity be
.
After the bumping the mass be M and it's velocity be V.
By law of conservation of momentum we have

2500 * 5 + 1500 * 1=4000 * V
V = 14000/4000 = 7/2 = 3.5 m/s
So the velocity of the two-car train = 3.5 m/s
Time = (distance) / (speed)
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Time = (450 km) / (100 m/s)
Time = (450,000 m) / (100 m/s)
Time = <em>4500 seconds </em>(that's 75 minutes)
Note:
This is about HALF the speed of the passenger jet you fly in when you go to visit Grandma for Christmas.
If the International Space Station flew at this speed, it would immediately go ker-PLUNK into the ocean.
The speed of the International Space Station in its orbit is more like 3,100 m/s, not 100 m/s.
Answer:
This question is about matching each definition with its correct term. Please find the term matched with their appropriate definition below.
Explanation:
1. Empirical evidence: An empirical evidence is an observational evidence i.e an evidence gathered by observation or use of senses.
2. Dependent variable: Dependent variable is an experimental factor that changes in response to a change in the independent variable. In other words, it is dependent on the independent variable.
3. Applied research: Applied research is a type of research oriented at solving a present problem or need. It encompasses the production of products that can be sold for profit.
4. Hypothesis: A hypothesis in an experiment is a proposed explanation for a scientific problem that itself can be tested by experimentation. A hypothesis aims at providing a testable explanation to an observed problem.
5. Control: A control is a quantity in an experiment that remains unchanged or constant. It is kept the same by the experimenter for all groups in the experiment in order not to influence the outcome.
6. Basic research: Basic research is the research that expands knowledge in a particular area. It is the kind of research that aims at filling a knowledge void or satiating curiosity.
7. Independent variable: The independent variable is the experimental factor that is changed or manipulated deliberately by the scientist.