What is the energy density of water stored at a height of 200 m in Megajoules per kilogram?

What is the energy density of water stored at a height of 200 m in Megajoules per kilogram?

• A. 19.6
• B. 0.0196
• C. 392,000
• D. 0.392

Answer: (B)

To determine the energy density of water stored at a height of 200 m, we can use the gravitational potential energy formula, which is given by: \[ \text{Potential Energy} = mgh \] where: - \( m \) is mass (in kilograms), - \( g \) is the acceleration due to gravity (approximately \( 9.81 \, \text{m/s}^2 \)), - \( h \) is the height (in meters). The energy density (energy per unit mass) can be calculated by dividing the potential energy by the mass \( m \). This simplifies our formula to: \[ \text{Energy Density} = gh \] Substituting the values into this equation: \[ g \approx 9.81 \, \text{m/s}^2 \] \[ h = 200 \, \text{m} \] So, \[ \text{Energy Density} = 9.81 \, \text{m/s}^2 \times 200 \, \text{m} = 1962 \, \text{J/kg} \] To convert this value to megajoules per kilogram, we recognize that 1 Megajoule

To determine the energy density of water stored at a height of 200 m, we can use the gravitational potential energy formula, which is given by:

[ \text{Potential Energy} = mgh ]

where:

• ( m ) is mass (in kilograms),

• ( g ) is the acceleration due to gravity (approximately ( 9.81 , \text{m/s}^2 )),

• ( h ) is the height (in meters).

The energy density (energy per unit mass) can be calculated by dividing the potential energy by the mass ( m ). This simplifies our formula to:

[ \text{Energy Density} = gh ]

Substituting the values into this equation:

[ g \approx 9.81 , \text{m/s}^2 ]

[ h = 200 , \text{m} ]

So,

[ \text{Energy Density} = 9.81 , \text{m/s}^2 \times 200 , \text{m} = 1962 , \text{J/kg} ]

To convert this value to megajoules per kilogram, we recognize that 1 Megajoule