Ans. Things only move if forced to move . So when something starts moving, there must be a force involved-whether it sis visible, like someone pushing, or gravity, which makes things fall. But once they are moving, things will carry on moving at the same speed and in the same direction, until another force is applied-typically friction.
Ans. This is Newton’s Third Law of Motion-for every action, there is an equal and opposite reaction. Which means that whenever something moves, there is a balance of forces pushing in opposite directions. When you push your legs against water to swim, for instance, the water pushes back on your legs equally hard.
Q4. What’s the difference between inertia and momentum?
Ans. Inertia is the tendency of things to stay still unless they are forced to move. Momentum is thee tendency for things to keep going once they are moving, unless forced to stop or slow. This is the First Law of Motion.
Ans. Sir Issac Newton’s breakthrough, in 1665, was to realize that all movement in the Universe is governed by three simple rules, which we now called Newton’s Law of Motion. the First is about inertia and momentum.
Ans. When something fixed in one place, called a fulcrum, is pushed or pulled elsewhere, it turns around the fulcrum. When you push a door shut, that push is the turning force, and the hinge is the fulcrum.
When two objects collide, their combined momentum remains the same, if nothing else interferes. So if one object loses momentum, this momentum must be passed on to the other object, making it move. This is essentially a knock-on effect.
Ans. Carbohydrates are chemicals made only of carbon, hydrogen and oxygen atoms-including sugars, starches and cellulose. Most animals rely on carbohydrates sugars such as glucose and sucrose for energy.
Ans. Carbon circulates like this: animals breathe out carbon dioxide. Plants take in carbon dioxide from the air, convert it into carbohydrates – and when animals eat plants, they take in carbon again.
Ans. Organic chemistry is the chemistry of carbon and its compounds. Carbon’s unique atomic structure means it links atoms together in long chains , rings or other shapes to form thousands of different compounds. These include complex molecules-such as DNA – that are the basis of life, which is why carbon chemistry is called organic chemistry.