A man of 50 kg is standing in a gravity free space at a height of 10m ...
Apply concept of centre of mass, since there is no Gravity in the space, centre of mass will remain stationary.
X being the position,
Xcom = 0 = (MmanXman + MstoneXstone) / (Mstone + Mman) .
Xman = – MstoneXstone/Mman .
Xman = – 0.5(10)/50 = – 0.1 metre.
When stone reaches 10 metres down, man moves 0.1 metres up with respect to inital position.
Thus, distance between man and floor is 10.1 metres.
A man of 50 kg is standing in a gravity free space at a height of 10m ...
Given:
Mass of the man (m₁) = 50 kg
Height of the man above the floor (h) = 10 m
Mass of the stone (m₂) = 0.5 kg
Initial velocity of the stone (v) = 2 m/s
To find:
Distance of the man above the floor when the stone reaches the floor.
Assumptions:
- The man and the stone are the only objects in the system.
- There is no air resistance or any other external forces acting on the system.
- The stone is thrown vertically downwards.
Step 1: Calculate the initial potential energy of the man:
Potential energy (PE) = mass (m) * gravity (g) * height (h)
PE₁ = m₁ * g * h
= 50 kg * 9.8 m/s² * 10 m
= 4900 J
Step 2: Calculate the initial kinetic energy of the stone:
Kinetic energy (KE) = 0.5 * mass (m) * velocity² (v²)
KE₂ = 0.5 * m₂ * v²
= 0.5 * 0.5 kg * (2 m/s)²
= 0.5 J
Step 3: Calculate the final kinetic energy of the stone:
Since the stone reaches the floor, its final kinetic energy is zero.
Step 4: Calculate the final potential energy of the man:
When the stone reaches the floor, the potential energy of the man will be equal to the initial potential energy of the man.
PE₁ = PE₂
m₁ * g * h = PE₂
50 kg * 9.8 m/s² * h = 4900 J
h = 10 m
Therefore, the distance of the man above the floor when the stone reaches the floor is 10 meters.
Explanation:
When the man throws the stone downwards, the stone loses its initial kinetic energy as it falls towards the floor. This lost kinetic energy is converted into potential energy. At the same time, the man loses an equal amount of potential energy as the stone falls. As a result, the man's distance above the floor remains constant throughout the stone's fall. Hence, when the stone reaches the floor, the man will still be 10 meters above the floor.
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