a body weighing 350N runs up a flight of stairs consisting of 20 steps each 10cm high in 10 second what is his power
find the electrical energy extended by an electrical lamp labelled 100w in 8 second
20 steps 0.10 meter high = 2 meters up (pathetic, just a hop and a skip)
m g h = gain in potential energy = 350 N * 2 meters = 700 Joules
power = Joules / seconds = 700 / 10 = 70 watts
energy in Joules = watts * seconds so 800 Joules for your lamp.
To calculate power, we need to know both the work done and the time taken.
First, let's calculate the work done. The work done is equal to the force applied multiplied by the distance covered:
Work = Force × Distance
The body's weight is given as 350N. The vertical distance covered by running up a flight of stairs can be calculated by multiplying the height of each step by the number of steps:
Distance = Height of each step × Number of steps
Given that each step is 10 cm high and there are 20 steps, the total vertical distance covered is:
Distance = 10 cm × 20 = 200 cm
Next, we need to convert the distance to meters since the SI unit of force is Newtons and the SI unit of distance is meters:
Distance = 200 cm ÷ 100 = 2 meters
Now, we can calculate the work done:
Work = 350N × 2 m = 700 J (Joules)
The work done is 700 Joules.
Finally, let's calculate power using the formula:
Power = Work ÷ Time
Given that the time taken is 10 seconds:
Power = 700 J ÷ 10 s = 70 Watts (W)
Therefore, the power exerted by the body is 70 Watts.