1). <u>Power = (voltage)² / (Resistance)</u>
4,500 = (220)² / Resistance
Multiply each side by (resistance) : 4,500 x resistance = (220)²
Divide each side by 4,500 : Resistance = (220)² / 4,500 = <em>10.76 ohms</em>
2). <u>Power = (voltage) x (Current)</u>
Divide each side by (voltage): Power / voltage = Current
4,500 / 220 = <em>20.45 Amperes</em>
3). 4,500 watts = 4.5 kilowatts
(4.5 kilowatts) x (4 hours) = <em>18 kilowatt-hours</em>
Helium atom, in other words, it consistis of a particle having four protons and two neutrons.
Answer:
Some lenses are used to focus light to a pre-defined point based on the amount of curvature of their surfaces.
In a piano design convex, some surfaces are flat while others has positive lenses (biconvex)
Explanation:
Solution
These lenses are applied to pay attention to light in a point pre-defined based on the amount of curvature of their surfaces.
For that of a plano-convex design, one surface has a positive curve and for biconvex lenses, both surfaces are positively curved while the other remains flat.
when used practically, plano-convex lenses are most commonly used where the object being imaged is far apart from lens.
Answer:The objects in order from least to greatest potential energy:
3<1<4<2
Explanation:
1. Potential energy of a 15-kilogram stone found at a height of 3 meters:

2. Potential energy 10 kilograms of water stored at a height of 9 meters:

3. Potential energy 1-kilogram ball located 20 meters in the air:

4. Potential energy box of books weighing 25 kilograms placed on a shelf 2 meters high:

The objects in order from least to greatest potential energy:
3<1<4<2