Answer:

Explanation:
Potential energy is energy due to position. It is the product of mass, height, and acceleration due to gravity.

The mass of the textbook is 1.85 kilograms. Assuming this is on Earth, the acceleration due to gravity is 9.8 meters per square second. The height is 2.23 meters.
- m= 1.85 kg
- g= 9.8 m/s²
- h= 2.23 m
Substitute the values into the formula.

Multiply the first 2 numbers together.

Multiply again.

- 1 kilogram square meter per square second (1 kg*m²/s²) is equal to 1 Joules (J)
- Our answer of 40.4299 kg*m²/s² is equal to 40.4299 J

The textbook has <u>40.4299 Joules of potential energy.</u>
Answer:
moles Fe₂O₃ = 0.938 mole
Explanation:
Convert given data to moles, solve in terms of moles by reaction ratios in balanced equation. After obtaining answer in moles, convert to needed dimension. In this case, no conversions are needed.
4Fe + 3O₂ => 2Fe₂O₃
105g/56g·mol⁻¹
= 1.875 mol Fe => => => => => => 2/4(1.875 mol Fe₂O₃) = 0.938 mol Fe₂O₃
Answer:
frequency of light = 
Explanation:
we know that relation between frequency and wavelength of light is
frequency × wavelength = speed of light.
therefore frequency = 
= 
=