Answer:
Digital thermometers.
Electronic ear thermometers.
Forehead thermometers.
Explanation:
NATURAL MAGNETS
A natural magnet is one that occurs naturally in nature. All natural magnet are permanent magnets , meaning they never lose their magnetic power.
Natural magnet can be found in Sandy deposits in various part of the earth .
The strongest natural magnetic material is LODESTONE also called magnetite.
ARTIFICIAL MAGNETS
These are magnets made by people.
It's these magnets that is in our refrigerator doors, which have extra-stronge magnetic power. There are two types of of artificial magnets. Temporary and Permanent Magnets.
Examples of artificial magnets are; electromagnet and the paper clip.
Examples of Permanent Magnets are; Alnico
<h3><u>Answer;</u></h3>
Mid-ocean ridges
<h3><u>Explanation</u>;</h3>
- Sea-floor spreading is the process by which molten material adds new oceanic crust to the ocean floor.
- Mid-ocean ridge is an undersea mountain chain where new ocean floor is produced at a divergent plate boundary.
- Mid ocean ridge occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary.
C. ultraviolet rays & D. gamma rays
None
Friction in Volleyball
Frication plays a huge role in every aspect of our lives; it can play a negative or positive role. In volleyball there are various types of friction that have positive influences on the way the game is played and there are others that play a negative role in the way the game is played.
Positive friction in volleyball.
In volleyball the aim of the game is to strike a ball into play that your opponent cannot return or finds it difficult to return. A friction force that makes this possible is the friction of the air on the ball, for example when a player hits a ball with topspin into play, the friction of the air on the ball makes it spin faster than it otherwise would. Topspin makes a ball harder to pick-up and pass to the setter.
Another force that is present is the ball itself, if there was no friction it would be virtually impossible to pass set, or hit the ball, the ball would just slip through your arms or hands.
When jumping a player also uses the frictions of their feet on the floor to gain a higher jump to strike the ball at maximal height, if this didn't exist players would be slipping and sliding around all over the court.
Negative friction in volleyball.
Friction also plays a negative part in the game of volleyball, when a player dives for a ball the friction of the court on their skin causes court burn or friction burn. Although the friction of the rubber soles of shoes on the court is a positive it can also be a negative, if there is too much friction players can become injured from the sudden stopping that the friction can cause. Some injuries that can result from this would be hyperextensions of the knees and or ankle injuries.
