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
The sweater has a tendency to attract electrons.
The leather jacket has a lower tendency to attract electrons than the sweater.
Explanation:
The sweater and the leather jackets are made up of distinct fabrics that based on their minutest particles called an atom.
An atom is made up of sub-atomic particles of protons, neutrons and electrons.
- Electrons occupies the bulk volume of the atom and they are easily lost in atoms that are big. They are negatively charged.
- Protons are positively charged and are very difficult to lose. They occupy the tiny nucleus with neutrons.
- A body that becomes negatively charged will be said to have a hihg tendency to attract electrons. Normally atoms are electrically neutral. When additional electrons are added to them, they become negatively charged.
- In this case, the sweater has a high affinity for electrons and it will attract the ones on the leather jacket.
- The leather jacket has a low tendency to attract electrons than the sweater and it will lose some of its electrons to the sweater.
Learn more:
Protons, neutrons and electrons brainly.com/question/2757829
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We may be positive that an object is in mechanical equilibrium if it is not rotating and experiences no acceleration.
<h3>What is
mechanical equilibrium?</h3>
There are numerous other definitions for mechanical equilibrium that are all mathematically comparable in addition to the definition in terms of force. A system is in equilibrium in terms of momentum if the component motions are all constant. If velocity is constant, the system is in equilibrium in terms of velocity. When an item is in a state of rotational mechanical equilibrium, its angular momentum is preserved and its net torque is zero. More generally, equilibrium is reached in conservative systems at a configuration space location where the gradient of the potential energy concerning the generalized coordinates is zero.
To learn more about mechanical equilibrium, visit:
<u>brainly.com/question/14246949</u>
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