Glaubst du denn wirklich, der Mond existiere nur, wenn du auf ihn blickst? (A. Einstein)
1. Two particles, each with a charge of 1 C, are separated by a distance of 1 meter. What is the force between the particles?
2. What is the force between a 3 C charge and a 2 C charge separated by a distance of 5 meters?
3. Calculate the force between a 0.006 C charge and a 0.001 C charge 4 meters apart. Read more
In 1832, Gauss strongly promoted the application of this Metric System as a coherent system of units for the physical sciences. Read more
«Many people are familiar with the daily routine of washing, drying and styling their hair. Although hair will eventually dry on its own if given enough time, most people reach for a hair-dryer to speed up the process. While science may have disproven the link between wet heads and catching colds, it’s still no fun to sit around with a head full of wet hair, especially in winter.
Hairy-dryers, also known as blow-dryers, were first sold in the 1920s. At first they were pretty dangerous to use – hundreds of people were electrocuted when they dropped their hair-dryer into water-filled sinks and bathtubs. Read more
The significant digits represent the valid digits of a number. The following rules summarize the significant digits:
Exercise 1. A filament has a diameter of 0.20 microns. Express this diameter in terms of a centimeter. (1 micron = 1 micrometer).
Exercise 2. Estimate the number of seconds in a human “lifetime”. We’ll let you choose the definition of “lifetime.”
Exercise 3. A cardboard box has a base that measures w = 1.92 m, and d = 0.725 m. If its height is h = 1.88 m. (a) Calculate the area of the base of the box. (b) Calculate its volume using the result of (a). (c) Calculate its volume using the formula for volume. Read more
