Velocity describes the speed and direction of an object. Speed tells how fast an object moves, but velocity is a vector measurement and includes both the rate and direction of an object's change of position.
The formula for calculating speed is distance traveled divided by time traveled. The formula for calculating velocity is the change of position, or displacement, divided by time. The difference between velocity and speed is more easily understood with the following example: a car completing a 10-mile course in 30 minutes has a speed of 20 miles per hour. If that car traveled at a speed of 20 miles per hour for five miles forward and then at the same speed for five miles in reverse, the velocity is zero because the car had no net displacement. It ended up in the same place it started.Learn More
Steam power works on the principle that heating water to the point of vaporization causes a build-up of pressure, because the vaporized water takes up more space than liquid water. Gases, liquids and solids are all held together by different molecular forces.Full Answer >
Gravity is important because it is the force the holds everything in the universe together. Although it is the weakest of the four known natural forces, it is the most dominant of those forces. No matter the size of an object, it has a gravitational force that extends through all space.Full Answer >
When a fish swims through water, it experiences drag caused by fluid friction. To swim successfully, a fish must use its strength to overcome resistance caused by friction. In clear waters, the water is quite thin, making swimming easier, but in murky waters, fish experience more friction, making swimming difficult.Full Answer >
The four main types of motion are translational, oscillatory, reciprocating and rotational motion. Some mechanisms use one type of motion for input but another type entirely for output.Full Answer >