You approach the door of your friends house. What is the first thing you do before entering? Of course, you wipe your feet. You are a thoughtful visitor. Fortunately, there is a nice piece of carpet by the door to wipe your shoes. Too bad your caring comes at a price. After wiping your feet on the mat you reach out to touch the brass knocker on the door. A spark suddenly jumps between your hand and the metal. You feel an electric shock. Why do you think an electric shock occurs? An electric shock occurs when there is a sudden discharge of static electricity. Has this ever happened to you? You reached out to touch a metal doorknob and received an unpleasant electric shock? The reason you get a shock is because of moving electric charges. Moving electric charges also create lightning bolts. It is also the same reason electric current flows through cables and wires.

Question: "When you approach a friends house, what is the first thing you do before entering?"

Response: "Wipe my shoes"

A: yes

It is not enough to describe some objects by their location. We may also need to know its direction. For example, a wind blows a storm over your school. Where is that storm coming from? Where is it going? How can we describe a direction? The most common way is by using a compass. A compass is a device with a floating needle (Figure 2.1). The needle is a small magnet. The needle aligns itself with the Earth's magnetic field. The compass needle always points to magnetic north. If you have a compass and you find north. You can then know any other direction. See the directions, such as east, south, west, etc., on a compass rose. The Earth has two poles. It has a magnetic north pole. It also has a geographic north pole. These two poles are close to each other but not the exact same place.

Question: "What is a compass?"

Response: "A compass is a device with a floating needle that is magnetic."

A: yes

The Venetian artist Jacopo de' Barbari, whom Durer had met in Venice, visited Nuremberg in 1500, and Durer said that he learned much about the new developments in perspective, anatomy, and proportion from him. De' Barbari was unwilling to explain everything he knew, so Durer began his own studies, which would become a lifelong preoccupation. A series of extant drawings show Durer's experiments in human proportion, leading to the famous engraving of Adam and Eve (1504), which shows his subtlety while using the burin in the texturing of flesh surfaces. This is the only existing engraving signed with his full name. Durer made large numbers of preparatory drawings, especially for his paintings and engravings, and many survive, most famously the Betende Hande (English: Praying Hands, c. 1508 Albertina, Vienna), a study for an apostle in the Heller altarpiece. He also continued to make images in watercolour and bodycolour (usually combined), including a number of still lifes of meadow sections or animals, including his Young Hare (1502) and the Great Piece of Turf (1503, both also Albertina).

Question: "What caused Durer to begin his own studies and experiment with human features in his art work?"

Response: "De'Barbari didn't want to explain all he knew"

A:
yes