Articles and letters may be edited for the purposes of clarity and space. They are published in good faith with a view to enlightening all the stakeholders. However, the contents of these writings may not necessarily match the views of the newspaper.
AC motor vs DC motor
Well AC, or Alternating Current motors are more efficient than DC or direct current. Both motors work by basically positive and negative current chasing itself in a circle which never catches up to itself so the motors turn. In AC, polyphase or three phase motors this becomes more efficient because you need lower current to do the same thing a DC motor does which requires more voltage to push it. But in a basic sense DC motors are good because you can control the speed of them better than AC.
You will find DC motors on things like rock crushers, car crushers etc., where there is a slow but constant speed needed despite the load. A DC motor may turn a conveyor belt at2 rpm’s but when you add rock or a crushing apparatus you will still get that 2 rpm despite the load. A lot of your home appliances ironically run on DC motors too. Now overload it then you will have problems but that is its basic uses today. AC motors you will find in factories because they have a faster startup speed and when you use the three phase motors they are just more efficient.
There is a type called a squirrel cage and then you can imagine the squirrel in the cage moving the rotor that chases the cage or the stator but never really goes end over end when doing so. That is the same principle of magnetism and voltage chasing current inside a DC or an AC motor but each are suited for uses where one or the other may not be as good given the circumstance or the operation you want to control.
M HAMZA ANWAR
Taxila Cant
A hospital’s woes
City Hospital Kashrote, Gilgit-Baltistan is one of the major hospitals of GB where tens of thousands of patients visit and get admitted on a daily basis. Building of this hospital is lofty and larger though, yet is devoid of basic facilities for patients.
In the chilling cold weather of GB, patients in this hospital are not even provided the blankets and pillows let alone heaters or other facilities to cope with atrocious weather. Most shockingly, the ICU wards lack the essential medical apparatus necessary to handle the emergency cases.
This is a huge risk for those emergency patients and severely wounded people who are carried to ICU expecting to save their lives. Chief Minister of GB is humbly being reminded that building a gigantic hospital building is a great initiative but, in addition, ensuring all facilities in it too is the genuine accomplishment.
ZAHID ALI ZOHRI
Nagar, Gilgit-Baltistan
APS attack
It was recently reported that the person caught for the bomb explosion outside Peshawar High Court this month, came from Afghanistan and was paid to cause an explosion on the eve of the cowardly and shameful APS attack. This person should be publicly executed in the most painful manner but not before finding out who paid him, so we know who was behind the APS attack.
For the people of Peshawar and our Armed Forces and for the families who lost their children that day 16th Dec 2014, the pain caused that day, can only be reduced if we expose the people involved and capture them and prosecute them and finally punish them in the most dreadful and painful way possible.
SHAHRYAR KHAN BASEER
Peshawar
Old age homes
Nobody on earth can ever love you more than your parents. In Pakistan, parents are considered as next to God. People consider it a sin to disobey them. Pakistani parents expect their children to look after them when they become old. When their son gets married, they are overjoyed by the arrival of their daughter-in-law, feeling more secure and comfortable.
Most Pakistani families respect their parents and take good care of them but unfortunately there are people who treat their parents as liabilities and make them feel neglected. Of course, there are rare cases when parents themselves prefer the privacy of old people’s home but in the majority of cases, it is the cold attitude of children that forces parents to move to old people homes. There is an unnecessary race for more money and luxuries which is intoxicating and shattering the family system. Children think they are doing nothing wrong to keep parents in an old people homes and that’s why demand for more such homes is increasing.
Our society’s values of taking care of old people are fading away. One often implies that the elderly are only counting down their days. Such comments about individuals who can still contribute much to society should be taken with a pinch of salt. Meanwhile, society itself needs to give serious thought to taking care of the needs of the elderly who have given them everything they have today.
AATIF KHAN
Islamabad
Insanity
In a sad incident, a groom was shot dead over a petty issue of filming the wedding participants in Peshawar. With the passage of time people have adapted themselves to the changing environment and adjusted with new norms of society. Filming of family members and relatives is not considered unethical. But the rigidity prevailing in some factions of society sometimes proves fatal.
The instant case has two-way impact; intolerance and access to weapons. Both bring disaster. Who will take care of widowed bride? Unfortunately, the brother-in-law of groom too, was involved in heinous act of murder. The gory act calls for strict action against those who take human lives on trivial issues.
IFTIKHAR MIRZA
Islamabad
Donate in winter
Karachi is sprawling with poor people. Many live on streets, around shrines and inside parks. The weather of Karachi is unpredictable. During winter, Karachi can get significantly cold enough. These poor people spend cold nights without shelter over their heads and make do with whatever clothes they have. They do not have comforters and shawls like many of us.
Owing to the recent economic conditions the city has become increasingly polarised where the rich are getting richer and the poor are dying. Being able members of society, we have to contribute whatever we can for those in need, not because they have less, but because as fellow human beings and for the sake of humanity it is our responsibility to help the needy. By doing so you are nothing more or nothing less.
Just the other day my friend met a boy on the road who was crying non-stop. When my friend asked the poor boy, he said that he was feeling really cold. This melted my friend’s heart and he decided to drop it back home after giving the boy the shawl my friend brought from Sehwan.
Try and give away anything warm you have lying around in your house that is not being used. Take out warm old clothes those that are not being worn anymore and donate them to those you see on the street. If God has blessed you with more, please buy some warm clothes and distribute them among those who need them most.
KHURAM JAMIL
Islamabad
Greta Thunberg — climate change activist
She is a student from a famous school in Sweden. Really and literally, the buck stops here. Greta Thunberg, a committed climate activist from Sweden has almost become the face of the world through her ambitious and rigorous protests against climate change crisis and all the failed policymakers and responsible stakeholders. In fact, people in parts of the world have been switching crop varieties [like banana, paddy, betel plantations] on a par with climate conditions.
Nothing has been done overnight in the corridors of this Swedish talented girl. Factually speaking, Thunberg has traversed a rough terrain so far only to have been humiliated by narrow-minded people from across the world for her extensive green mission. In fact, being a student, she might have bunked off school and maybe could have flunked school exams/subjects only to have been holding numerous climate strikes across the world to date for the sake of a much better world in future.
Given her speculative talks and informative discussions on climate crisis across so many platforms and on TV and now that she has been having a great understanding of climate change and its far-reaching consequences, Greta Thunberg has been overwhelmingly made the Time 2019 Person Of The Year. The fact is that Time has been vastly piling more accolades on Thunberg, featuring and writing articles about her almost on a daily basis. Above all, she has been a source of inspiration for so many people worldwide today, all for a better, a much better world tomorrow.
P SENTHIL S DURAI
Via email
Clinching top positions
It is really a matter of delight to see that female students have clinched top positions in all faculties of Karachi University. Whether it is result of HSC or FCS every year female students are seen taking top positions. Where it is delightful moment for the nation that our females are not far behind at all in all the fields especially in education field as well as it is a matter of grave concern that what male students are doing and where their time is spent. If it keeps going that female students beat male students in securing top positions, soon there would be imbalance in the society observed that females would be found much qualified than males.
If a survey is carried out in Karachi where education ratio is better than other cities of Pakistan, it would be known that in each house approximately two to three females are waiting for suitable proposals for getting married only because either males are unemployed or if they are employed found earning low salary. Food for thought is to encourage males of the society through brainstorming to study well so that equilibrium society might be established and men and women stand side by side.
FAISAL ANSAR
Karachi