How much work is done by a person lifting a 2 kg object from a bottom of a well at constant speed of 2 m\ s for 5 sec
Well, let's see. If the person is lifting the object at a constant speed, that means there is no change in the object's potential energy. So, no work is actually done on the object. However, the person doing the lifting sure is getting a workout! So, I'd say the amount of work done by the person is equal to the number of calories they burned lifting that object, which is probably not much, let's be honest. But hey, at least they got a little exercise!
To calculate the work done, we need to use the formula:
`Work = Force × Distance × cos(θ)`
Here, the force is equal to the weight of the object, which can be calculated using the formula:
`Force = Mass × Acceleration due to gravity`
Acceleration due to gravity is approximately 9.8 m/s^2.
Given:
Mass of the object (m) = 2 kg
Distance lifted (d) = 2 m
Speed (v) = 2 m/s
Time (t) = 5 s
First, let's calculate the force:
`Force = 2 kg × 9.8 m/s^2 = 19.6 N`
Since the person is lifting the object at a constant speed, there is no change in kinetic energy, which means no work is done against gravity. The work is only done to overcome the gravitational force.
Now, let's calculate the work:
`Work = Force × Distance × cos(θ)`
Here, the angle (θ) between the force applied and the direction of displacement is 0 degrees (cos(0) = 1).
`Work = 19.6 N × 2 m × cos(0)`
`Work = 19.6 N × 2 m × 1`
`Work = 39.2 J`
Therefore, the work done by the person lifting the 2 kg object from the bottom of the well at a constant speed of 2 m/s for 5 seconds is 39.2 Joules.
To calculate the work done by a person lifting the object, we need to use the formula:
Work = Force × Distance
The force used to lift the object can be calculated by using Newton's second law of motion:
Force = mass × acceleration
In this case, the mass of the object is given as 2 kg, and the acceleration can be calculated by dividing the constant speed by the time taken:
Acceleration = speed / time
Given that the speed is 2 m/s and the time is 5 seconds, we have:
Acceleration = 2 m/s / 5 s
Now, let's calculate the acceleration:
Acceleration = 2 m/s / 5 s = 0.4 m/s^2
Using the formula for force, we can calculate the force required to lift the object:
Force = mass × acceleration = 2 kg × 0.4 m/s^2 = 0.8 N
Now that we know the force, we can calculate the work done by multiplying it with the distance lifted. The distance is not mentioned in the question, so it needs to be provided in order to calculate the work done.