Answer all for full points what is gravity? what are the three types of contact forces and what is an example of each? how are electricity and magnets connected? what is the difference between a balanced and an unbalanced force? give an example of each. what are si units, and why are they used?

gravity is the invisible force that attracts us the the earth\

1.normal force 2.frictional force 3. spring forces

flowing electrons produce a magnetic field

unbalanced forces are not equal they always cause changes in the moving object like the direction . balanced forces are equal and cause no changes

The SI system, also called the metric system, is used around the world. There are seven basic units in the SI system  the meter kilogram  second (s), kelvin  the ampere , the mole  and the candela.

heats surface water up

a=d/t

a="triangle"v/t

explanation:

a = acceleration