A brick of mass [tex]$2.3 \, \text{kg}$[/tex] is lifted to a height of [tex]$1.9 \, \text{m}$[/tex]. How much gravitational potential energy is added to the brick? The acceleration due to gravity is [tex]g = 9.8 \, \text{m/s}^2[/tex].

A. [tex]98.5 \, \text{J}[/tex]
B. [tex]42.8 \, \text{J}[/tex]
C. [tex]4.37 \, \text{J}[/tex]
D. [tex]0.45 \, \text{J}[/tex]



Answer :

To solve for the gravitational potential energy added to a brick when it is lifted to a certain height, we use the formula for gravitational potential energy:

[tex]\[ U = mgh \][/tex]

where:
- [tex]\( m \)[/tex] is the mass of the brick,
- [tex]\( g \)[/tex] is the acceleration due to gravity,
- [tex]\( h \)[/tex] is the height to which the brick is lifted.

Given:
- Mass of the brick, [tex]\( m = 2.3 \)[/tex] kg,
- Height, [tex]\( h = 1.9 \)[/tex] m,
- Acceleration due to gravity, [tex]\( g = 9.8 \)[/tex] m/s[tex]\(^2\)[/tex].

Now, substituting the given values into the formula:

[tex]\[ U = (2.3 \text{ kg}) \times (9.8 \text{ m/s}^2) \times (1.9 \text{ m}) \][/tex]

First, multiply the mass and gravity:

[tex]\[ 2.3 \times 9.8 = 22.54 \][/tex]

Next, multiply the result by the height:

[tex]\[ 22.54 \times 1.9 = 42.826 \][/tex]

Thus, the gravitational potential energy added to the brick when it is lifted to a height of 1.9 meters is:

[tex]\[ U \approx 42.8 \text{ J} \][/tex]

Therefore, the correct answer is:

B. [tex]\( 42.8 \text{ J} \)[/tex]