The Human Body your body is made up of trillions of cells? Different parts of your body are made of different kinds of cells. ...your brain is like a computer, and controls your entire body? ...your heart beats about 70 times a minute, and each time it beats, it pumps about about a cupful of blood? ...an adult human heart weighs about 10 ounces and beats over 100,000 times a day? ...there are 206 bones in your skeleton? ...about half of the bones in the human body are located in the hands and feet? ...everyone has thirty-two teeth? ...your muscles make up about one-half of your body weight? ...if you were to remove your skin, it would weigh as much as 5 pounds? ...about 70 percent of your body weight is water? ...physics includes the study of light, magnets, electricity, forms of energy, sound, mechanics (studying the action of forces on matter)? ...objects and people move and obey three basic laws of motion: inertia, mass and force, action and reaction? ...inertia, the first law of motion, states that objects that are at rest tend to stay at rest unless acted upon by some outside force? A ball will not move unless someone kicks it. ...the second law of motion deals with the mass (the amount of matter in an object) and force (the action on an object)? A ball does not speed up or slow down all by itself because it takes a force to move it or slow it down. How the ball moves depends upon the the object that is used to move it, the force used to move it, and the direction of the force. ...the third law of motion, action and reaction, states that for every action their is an equal or opposite reaction? A person on a skateboard pushes back to accelerate, and his push back on the ground sends him forward on his skateboard. ...Isaac Newton discovered the laws of motion more than 300 years ago?
