The new iPad unveiled Wednesday comes with improvements that may not be readily apparent to the casual observer. It has, as expected, a sharper screen, driven by a faster processing chip that acts as the “brains” of the device. What was more surprising was that the new features mean the tablet computer will be slightly thicker and heavier than the iPad 2, because it needs a larger battery to power the high-resolution screen. Apple gave the new iPad a bunch of new features but no new name. It will be “the iPad” or perhaps “the new iPad“, not “iPad 3” or “iPad HD,” as some had speculated. The battery life of the new model remains the same: about 10 hours of use. Apple says the battery capacity is 70 percent higher than for the old model, which suggests that it could have kept the old screen and extended the battery life to 17 hours instead of upgrading the screen resolution. As reported Apple the new display will be sharper than the average high-definition television set. The higher resolution won’t make a difference, however, for most Web images, which are of low resolution. The new screen should be able to show all the detail in high-definition movies, which the iPad 2 does not. The new screen can also show deeper and more vibrant colors than previous models. The new iPad will be 9.4 millimeters thick, or 0.37 inches. That compares with 8.8 millimeters, or 0.34 inches, for the iPad 2. The weight is going up from 1.33 pounds to 1.44 pounds for the Wi-Fi only model. The original iPad weighed 1.5 pounds. The new iPad will go on sale March 16 in the U.S., Canada and 10 other countries. A week later, it will go on sale in 25 more countries. Prices aren’t changing from the previous models. They will start at $499. Versions capable of accessing cellular networks will cost $629 to $829. Apple is keeping the basic model of the iPad 2 in production and dropping the price to $399.