A man stands on a weighing machine placed on a horizontal platform. Th...
Here, m = 50kg, v = 2s
-1a = 5 cm = 0.05m
Max. acceleration, a
max = ω
2a
∴ Max. force on the man
Mini. force on the man
View all questions of this test
A man stands on a weighing machine placed on a horizontal platform. Th...
Effect of Harmonic Vibrations on the Reading of the Weighing Machine
The effect of harmonic vibrations on the reading of the weighing machine can be analyzed by considering the forces acting on the man and the platform during the vibrations.
1. Forces acting on the man:
The man experiences two types of forces while standing on the weighing machine:
- Gravitational force (mg): This force always acts vertically downwards and is constant.
- Normal force (N): This force is exerted by the weighing machine to balance the gravitational force and prevent the man from sinking into the machine. It is equal in magnitude and opposite in direction to the gravitational force.
2. Forces acting on the platform:
The platform undergoes harmonic vibrations with a frequency of 2 vibrations per second and an amplitude of 5 cm. As a result, the platform experiences an oscillating vertical displacement.
- Spring force (Fs): The spring force acts in the opposite direction to the displacement of the platform. It is given by Hooke's Law: Fs = -kx, where k is the spring constant and x is the displacement of the platform from its equilibrium position. The spring force varies sinusoidally with time as the platform oscillates.
- Inertia force (Fi): The inertia force acts in the same direction as the displacement of the platform and is given by Fi = mω²x, where m is the mass of the platform and ω is the angular frequency of oscillation (2πf).
3. Effect on the reading of the weighing machine:
The reading on the weighing machine is determined by the balance between the gravitational force and the normal force. As the platform oscillates, the normal force will vary due to the forces acting on the platform. This will result in a variation in the reading of the weighing machine.
- When the platform is at its extreme positions, the spring force is maximum and the inertia force is minimum. At these positions, the normal force will be greater than the gravitational force, leading to an increase in the reading of the weighing machine.
- When the platform is at its equilibrium position, the spring force and the inertia force are zero. At this position, the normal force will be equal to the gravitational force, resulting in the correct reading of the weighing machine.
- When the platform is at the mid-positions between the extreme positions, the spring force and the inertia force are both present but in opposite directions. The normal force will be less than the gravitational force, leading to a decrease in the reading of the weighing machine.
Considering the given options, it can be concluded that the effect on the reading of the weighing machine will be between 10.5 kg force and 89.5 kg force.
A man stands on a weighing machine placed on a horizontal platform. Th...
Here, m = 50kg, v = 2s
-1a = 5 cm = 0.05m
Max. acceleration, a
max = ω
2a
∴ Max. force on the man
Mini. force on the man