Objects move because a force is acting on them, either pushing or pulling. They fall because the force of gravity pulls them towards the Earth. Forces tend to make objects accelerate, and gravity is no exception. The speed of a free-falling object, however, will depend on several factors.
A tennis-ball dropped over a high-rise building, for example, accelerates at roughly 32 feet per second. This means that each second the ball moves 32 feet per second faster than the second before. The ball is stationary at 0 feet person second. At the end of 1 second, it is traveling at 32 feet per second. At the end of 2 seconds, it moves at 64 feet per second. At the end of 3 seconds, 96 feet per second and so on. In fact, every second it travels 32 feet per second faster.
One of the important points to note about falling objects is that however heavy they are, they all fall at the same rate. The famous Italian scientist Galileo Galilei is reputed to have proven this by dropping a heavy cannonball and a light musket ball at the same time from a wall. Both objects arrived at the ground at the same time.
Air resistance is the main reason why some objects fall faster than others. A feather, for example, floats slowly downwards because it has a relatively large surface for the air to act on. A smooth, pointed bullet will fall faster than a feather because it cuts cleanly through the air. Because of the air resistance experienced by all objects as they fall, the rate of acceleration will always be slightly reduced. Only in vacuum are the figures quoted above exactly true.
The discussion above is a basic one for those interested in physics. Below are a few kits that can help children develop an interest in this subject:
This is a physics kit that contains hundreds of building pieces to stimulate a child’s mind. With these three hundred and more pieces, one can build several items including a hammer machine, a two-speed crane, a windmill, and much more. The activity will help us experiment and recreate simple machines, understanding the working of gears, wheels, axles, pulley, and inclined planes along the way.
The package also contains a fully-colored manual consisting of 64 pages. This is designed to help us understand basic physics equations and make us interested in learning even more. Many reviewers have reported that their young kids love this kit and are able to construct several models with the given instructions.
Finally, the parts are also quite sturdy and not too small for a child to handle. These are important features, as kids need to learn and understand the fitting and working on their own as much as possible. Unfortunately, there are some reports about the instructions being a little vague, so you might have to take some help from the internet in such cases. This isn’t necessarily a bad thing, as you can then quickly look up answers to questions such as whether things are lighter or heavier when they’re hot or cold.
This is a basic learning starter kit that focuses on electricity and magnetism experimentation. It’s suitable for kids in junior classes as well as those in high school. By experimenting and conducting the activities here, young minds will be able to absorb the principles of basic circuits. There are around 50 items inside, with a 40-page manual guiding us through the steps of each experiment.
The manual here is clearly illustrated and focused on encouraging critical thinking. If your child is constantly asking questions like why are astronauts weightless in space, this kit will encourage and develop their interest more.
This is another science kit that can help us create several items for understanding and learning about scientific subjects. Making a Newton’s Cradle or a DIY pulley crane, for instance, will give kids an introduction to engineering, circuit building, mechanics, and more.