Answer :
To find the gravitational potential energy added to a brick when it is lifted to a certain height, you use the formula for gravitational potential energy (GPE):
[tex]\[ \text{GPE} = m \times g \times h \][/tex]
where:
- [tex]\( m \)[/tex] is the mass of the object in kilograms (kg),
- [tex]\( g \)[/tex] is the acceleration due to gravity in meters per second squared (m/s²), and
- [tex]\( h \)[/tex] is the height in meters (m).
For this problem:
- The mass [tex]\( m \)[/tex] of the brick is 2.3 kg,
- The acceleration due to gravity [tex]\( g \)[/tex] is 9.8 m/s²,
- The height [tex]\( h \)[/tex] is 1.9 m.
Substituting these values into the formula gives:
[tex]\[ \text{GPE} = 2.3 \, \text{kg} \times 9.8 \, \text{m/s}^2 \times 1.9 \, \text{m} \][/tex]
[tex]\[ \text{GPE} = 42.826 \, \text{J} \][/tex]
Rounding this to an appropriate number of significant figures, the gravitational potential energy is approximately 42.8 J.
Thus, the correct answer is B. 42.8 J.
[tex]\[ \text{GPE} = m \times g \times h \][/tex]
where:
- [tex]\( m \)[/tex] is the mass of the object in kilograms (kg),
- [tex]\( g \)[/tex] is the acceleration due to gravity in meters per second squared (m/s²), and
- [tex]\( h \)[/tex] is the height in meters (m).
For this problem:
- The mass [tex]\( m \)[/tex] of the brick is 2.3 kg,
- The acceleration due to gravity [tex]\( g \)[/tex] is 9.8 m/s²,
- The height [tex]\( h \)[/tex] is 1.9 m.
Substituting these values into the formula gives:
[tex]\[ \text{GPE} = 2.3 \, \text{kg} \times 9.8 \, \text{m/s}^2 \times 1.9 \, \text{m} \][/tex]
[tex]\[ \text{GPE} = 42.826 \, \text{J} \][/tex]
Rounding this to an appropriate number of significant figures, the gravitational potential energy is approximately 42.8 J.
Thus, the correct answer is B. 42.8 J.
