Answer:
Explanation:
The work done on a particle by external forces is defined as:
According to Newton's second law 
. Thus:
Acceleration is defined as the derivative of the speed with respect to time:
Speed is defined as the derivative of the position with respect to time:
Kinetic energy is defined as 
:
Some of the forms of energy are: heat energy, mechanical energy, gravitational energy, electrical energy, sound energy, chemical energy, nuclear or atomic energy <span>and so on. Some examples of this are:
</span>Heat energy: the sun in our solar system. Mechanical energy: a moving car. Gravitational energy: a pen being held above a table. Electrical energy: lightning. Sound energy: musical Instruments. Chemical energy: batteries. Nuclear or atomic energy: the fusion reaction in the sun.
Answer:
metal and non-metal
Explanation:
Ionic bonds are formed when a metal loses electrons and a non-metal gains said electrons.
If the sign of work is negative, that means the force and the motion are in opposite directions.
Let's say you see something roll off of the shelf. You catch it, and you let it down slowly and gently.
Gravity exerted down-force on it and it moved down. Gravity did positive work on it.
YOU exerted UP-force on it and it moved down. YOU did negative work on it.
(Also, the falling object exerted down-force on your hand, and your hand moved down. The falling object did positive work on your hand ! Where did THAT energy come from ? It came from the potential energy that the object had while it was on the shelf. Your hand absorbed that energy on the way down, doing negative work. So the object didn't have any kinetic energy when it reached the floor, and it did NOT splinter the floor or shatter in smithereens. It had barely enough energy left to make a sound when it hit the floor.)
Improved muscle strength and tone – to protect your joints from injury.
maintaining flexibility and balance, which can help you remain independent as you age.
weight management and increased muscle-to-fat ratio – as you gain muscle, your body burns more kilojoules when at rest.
