QUES: The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo). Early carbon filaments had a negative temperature coefficient of resistance as they got hotter, their electrical resistance decreased. This made the lamp sensitive to fluctuations in the power supply, since a small increase of voltage would cause the filament to heat up, reducing its resistance and causing it to draw even more power and heat even further. In the "flashing" process, carbon filaments were heated by current passing through them while in an evacuated vessel containing hydrocarbon vapor (usually gasoline). The carbon deposited on the filament by this treatment improved the uniformity and strength of filaments as well as their efficiency. A metallized or "graphitized" filament was first heated in a high-temperature oven before flashing and lamp assembly. This transformed the carbon into graphite which further strengthened and smoothed the filament. This also changed the filament to have a positive temperature coefficient, like a metallic conductor, and helped stabilize the lamp's power consumption, temperature and light output against minor variations in supply voltage.

What properties of graphite improved the filament?
What is the answer?
ANS: further strengthened and smoothed the filament
QUES: Psychological anthropology is an interdisciplinary subfield of anthropology that studies the interaction of cultural and mental processes. This subfield tends to focus on ways in which humans' development and enculturation within a particular cultural groupwith its own history, language, practices, and conceptual categoriesshape processes of human cognition, emotion, perception, motivation, and mental health. It also examines how the understanding of cognition, emotion, motivation, and similar psychological processes inform or constrain our models of cultural and social processes.

What shapes cultural groups?
What is the answer?
ANS: unanswerable
QUES: Football is largely considered the Nigeria's national sport and the country has its own Premier League of football. Nigeria's national football team, known as the "Super Eagles", has made the World Cup on five occasions 1994, 1998, 2002, 2010, and most recently in 2014. In April 1994, the Super Eagles ranked 5th in the FIFA World Rankings, the highest ranking achieved by an African football team. They won the African Cup of Nations in 1980, 1994, and 2013, and have also hosted the U-17 & U-20 World Cup. They won the gold medal for football in the 1996 Summer Olympics (in which they beat Argentina) becoming the first African football team to win gold in Olympic Football.

What country did Nigeria beat to win a Summer Olympics gold medal?
What is the answer?
ANS:
Argentina