Question
A mail carrier lifts a box that weighs 72 N. The box is lifted a height of 0.9 m. How much work did the mail carrier do?
Group of answer choices
80.0 J
72.1 J
99.2 J
64.8 J
Group of answer choices
80.0 J
72.1 J
99.2 J
64.8 J
Answers
GPT-4o mini
Work can be calculated using the formula:
\[ \text{Work} = \text{Force} \times \text{Distance} \times \cos(\theta) \]
In this case, the force is the weight of the box (72 N), the distance is the height it is lifted (0.9 m), and since the force is applied vertically upwards and the distance is also in the vertical direction, \(\theta = 0^\circ\) (which means \(\cos(0^\circ) = 1\)).
Thus, the calculation simplifies to:
\[ \text{Work} = \text{Force} \times \text{Distance} \]
Now substituting the values:
\[ \text{Work} = 72 \, \text{N} \times 0.9 \, \text{m} \]
Calculating:
\[ \text{Work} = 64.8 \, \text{J} \]
Thus, the mail carrier did **64.8 J** of work.
The correct answer is: **64.8 J**.
\[ \text{Work} = \text{Force} \times \text{Distance} \times \cos(\theta) \]
In this case, the force is the weight of the box (72 N), the distance is the height it is lifted (0.9 m), and since the force is applied vertically upwards and the distance is also in the vertical direction, \(\theta = 0^\circ\) (which means \(\cos(0^\circ) = 1\)).
Thus, the calculation simplifies to:
\[ \text{Work} = \text{Force} \times \text{Distance} \]
Now substituting the values:
\[ \text{Work} = 72 \, \text{N} \times 0.9 \, \text{m} \]
Calculating:
\[ \text{Work} = 64.8 \, \text{J} \]
Thus, the mail carrier did **64.8 J** of work.
The correct answer is: **64.8 J**.