Suppose you lift a laptop that weighs 4.6 pounds off the floor onto a shelf that is 4 feet high. How much work have you done?
The amount of work done is equal to the force applied multiplied by the distance moved. In this case, the force applied is 4.6 pounds and the distance moved is 4 feet. Therefore, the amount of work done is 18.4 foot-pounds.
To calculate the work done in this scenario, we can use the formula:
Work = Force x Distance
Here, we need to determine the force and distance involved. The force can be calculated using the weight of the laptop, and the distance is the height of the shelf.
1. First, convert the weight of the laptop from pounds to force in Newtons. The conversion factor is approximately 4.45 N per pound.
Weight = 4.6 pounds ≈ (4.6 pounds) × (4.45 N/pound) ≈ 20.57 N
2. Now, we need to calculate the distance lifted. Since it is mentioned that the shelf is 4 feet high, we need to convert this distance to meters, as the SI unit of force is Newtons and the SI unit of distance is meters.
Distance = 4 feet × (0.3048 meters/foot) ≈ 1.2192 meters
3. Finally, we can calculate the work:
Work = Force x Distance
Work = 20.57 N × 1.2192 meters ≈ 25.07 Joules
Therefore, you have done approximately 25.07 Joules of work in lifting the laptop onto the shelf.
To determine the amount of work done, we can use the formula:
Work = Force × Distance
In this case, the force required to lift the laptop is equal to its weight, which is 4.6 pounds. To convert it to pounds-force, we multiply by the acceleration due to gravity, which is approximately 32.2 ft/s². Thus, the force can be calculated as follows:
Force = 4.6 pounds × 32.2 ft/s²
Next, we need to determine the distance over which the laptop is lifted. In this case, it is 4 feet. However, we need to convert it to the same unit as the force, which is feet. Thus, the distance is:
Distance = 4 feet
Now, we can calculate the work done using the formula:
Work = Force × Distance
Work = (4.6 pounds × 32.2 ft/s²) × 4 feet
By performing the calculations, the work done can be determined.