key = K_BACKSPACE : if len ( text ) > 0 : text = text else : text += event. height )) running = True background = GRAY while running : for event in pygame. These concepts are independent of the type of force. The apple now has less gravitational potential energy. topleft = ( 20, 20 ) cursor = Rect ( rect. For example, if an apple is dropped from the branch of a tree, the force of gravity does work to move (accelerate actually) the apple from the branch to the ground. set_mode (( 640, 240 )) text = 'this text is editable' font = pygame. """Edit text with the keyboard.""" import pygame from pygame.locals import * import time BLACK = ( 0, 0, 0 ) RED = ( 255, 0, 0 ) GRAY = ( 200, 200, 200 ) pygame. get_fonts () print ( len ( fonts )) for i in range ( 7 ): print ( fonts ) running = True background = GRAY while running : for event in pygame. render ( 'didot.ttc', True, GREEN ) fonts = pygame. SysFont ( 'didot.ttc', 72 ) img2 = font2. render ( 'chalkduster.ttf', True, BLUE ) font2 = pygame. SysFont ( 'chalkduster.ttf', 72 ) img1 = font1. rect ( img, BLUE, rect, 1 ) font1 = pygame. render ( sysfont, True, RED ) rect = img. SysFont ( None, 48 ) print ( 'time needed for Font creation :', time. get_default_font () print ( 'system font :', sysfont ) t0 = time. So, to study the cool cosmos, infrared light is our window into the heat of the coolest things around."""Draw text to the screen.""" import pygame from pygame.locals import * import time BLACK = ( 0, 0, 0 ) RED = ( 255, 0, 0 ) GREEN = ( 0, 255, 0 ) BLUE = ( 0, 0, 255 ) GRAY = ( 200, 200, 200 ) pygame. Clouds of dust that range from hundreds to tens of degrees above absolute zero appear as black soot in visible light, but glow brightly at infrared wavelengths out to several hundred microns.
A micron is a millionth of a meter.Īstronomers who want to study the most frigid things in the Universe turn to infrared telescopes to reveal their faint glow. People, who are much cooler (310 K, 98° F), actually glow as well, but in infrared light with a wavelength of around 10 microns. Our Sun's temperature is a blistering 5,778 K (9,940° F), which is so hot that it glows brightest at visible wavelengths of light (around 0.4 - 0.7 microns). Scientists measure temperature using the Kelvin temperature scale.Ĭooler objects glow faintly at longer wavelengths of light, while hotter objects glow more brightly at shorter wavelengths. You can recreate Herschel's experiment yourself with a box, a prism, three thermometers, and a few other common supplies.
He hypothesized that there must be more light beyond the color red that we simply could not see with our own eyes. Unexpectedly, he found the thermometer showed a rise in temperature, even when placed in the dark area beyond the edge of the red light. He split light into a rainbow (called a spectrum) by passing sunlight through a prism, and then placed a thermometer in different colors in that spectrum. Sir William Herschel first discovered infrared light in 1800. Infrared light falls just outside the visible spectrum, beyond the edge of what we can see as red. But visible light, the only light our eyes can see, makes up just a tiny sliver of all the light in the world around us. When we think of light, we may imagine the glare of the Sun on a summer day, or the soft glow of a light bulb at night.
light that we can not see with our eyes, but that we can sometimes feel on our skin as heat.