a uniform rectangular marble slab is 3.4m long and 2.0 m wide with a mass of 180kg. it is lyning on flat ground how much work is needed to stand it on end
3.0 kj
To calculate the work needed to stand the marble slab on end, we need to consider the change in potential energy. When the slab is lying flat on the ground, its center of mass is at its lowest point, resulting in zero potential energy. When the slab is standing on end, its center of mass will be raised to a certain height, creating potential energy.
The potential energy (PE) can be calculated using the formula:
PE = m * g * h
Where:
m = mass of the slab (180 kg)
g = acceleration due to gravity (9.8 m/s^2)
h = change in height (difference between the initial and final heights)
Since the slab is standing on end, we need to find the change in height. When the slab is lying flat, the height is zero. When standing on end, the height will be the length of the slab, 3.4 meters.
h = 3.4 meters
Now, we can calculate the potential energy:
PE = m * g * h
= 180 kg * 9.8 m/s^2 * 3.4 m
= 5911.2 joules (J)
Therefore, the work needed to stand the marble slab on end is approximately 5911.2 joules.