To do that, you must pass electric current through a substance
that electrons have to spend energy to pass through.
The substance will be one that gets warm and dissipates heat
when electric current flows through it.
We'll say that the substance has "resistance", which we can measure.
The amount of heat that appears when current flows through it
will be (current²)·(resistance).
A few examples of things used for that purpose:
-- resistors
-- burners on electric stoves
-- coils of resistor-wire in a toaster
-- aquarium heater
-- electric clothes iron
-- electric coffee pot
-- blow-dryer
-- electric hair-curling iron
-- skinny tungsten wire in a light-bulb .
Answer:
B
Explanation:
Speed is the magnitude of the velocity vector, so it can never be negative.
Answer:

Explanation:
Force can be found by multiplying the mass by the acceleration.

The mass of the roller coaster is 2000 kilograms and the acceleration is 2 meters per second squared.

Substitute the values into the formula.

Multiply.

- 1 kg*m/s² is equal to 1 N
- Therefore our answer of 4000 kg*m/s² is equal to 4000 Newtons

The net force acting on the roller coaster is <u>4000 Newtons.</u>
Answer:
Granite
Explanation:
Trust me I learned this 2years ago
Density applies to many if not all aspects of life. With density you can explain why ice floats. You can explain why oxygen is on the earth, and not floating around in space( or being replaced by another gas). You can also explain why heat rises while cold air sinks.