Up To Physics: A "Big Bang Theory" Quiz

Answer: 360

This was first mentioned in the very first episode "Pilot". Leonard and Sheldon are outside Kurt's building trying to get inside so they can get Penny's TV back. They fail to find a way themselves, but grab the door when two girls selling cookies find a way inside easily.

Answer: Mary Cooper

Mrs Cooper is first seen in "The Luminous Fish Effect", which is episode 4 in series 1. Sheldon has been fired from his job and starts getting depressed, so Leonard phones his mother and she comes out to try and snap him out of it. Mary Cooper is played by Laurie Metcalf.

Answer: Norse God Thor

Penny's Halloween party was in the sixth episode, "The Middle-Earth Paradigm". Howard went as Robin Hood, although everybody thought he was Peter Pan. Leonard went as Frodo from "The Lord of The Rings", and Sheldon went as The Doppler Effect, which nobody understood.

Answer: The Dumpling Paradox

Mrs Wolowitz (played by Carol Ann Susi) was never seen properly on screen. We only ever heard her voice. In some later episodes, we saw a huge body from a distance, which shows that she was a big person, as mentioned a lot by Howard, but we never saw her face.

Answer: Soft Kitty

"Soft Kitty" has become one of the running jokes of the show when Sheldon is sick. It came about when Sheldon's mother used to sing this to him as a young boy when he was sick. It was first shown on screen in "The Pancake Batter Anomaly", when Sheldon catches germs from Penny and becomes sick. Penny is the unfortunate person who has to look after him and who sings him "Soft Kitty".

Answer: PMS and AA

This was in the episode "The Bat Jar Conjecture", when Sheldon decided to leave Leonard's team and make his own. Leonard, Raj, Howard and Leslie called their team PMS (Perpetual Motion Squad) and Sheldon called his team AA (Army Ants).

Answer: $800

He only bid that much as he believed it would go for thousand, and he just wanted to be part of it. He also believed it to be a miniature version, but it turned out to be a full size time machine. Howard, Sheldon and Raj all paid $200 each and they all became joint owners. This was the fourteenth episode, "The Nerdvana Annihilation".

Answer: Leonard

Leonard had previously told Penny at the start of the episode that he had never had a birthday party, so she decides that she will throw him one. To distract Leonard and get him out of the apartment, Howard pretends to eat peanuts, which he is allergic to, but when this fails, he is forced to eat a bar which has peanuts in it.

By the time Leonard and Howard get back to the apartment, the party has finished and they have missed it all.

Answer: Mandarin

Sheldon believes the Chinese restaurant is selling tangerine chicken but are using oranges, and he intents to confront them by speaking Mandarin. This is also the episode when Leonard asks Penny out on a date, and they both know it is a date (Leonard and Penny went for a meal earlier in the series, but only Leonard saw it as a date).

This is the final episode in the series, "The Tangerine Factor".

Answer: It is never mentioned in season 1

For every other main character, we know all of their surnames, but Penny we never find out what her last name is in this series.