Laptop Freefall Protection: How Sensors Detect Falls

[Ranku]

An object in gravitational freefall cannot sense its own acceleration. As you know some laptops come with hard-disk protection that 'seizes up' the hard-disk when the laptop takes a tumble from your table. How do the sensors in the laptop detect it is falling?

 

[phyzguy]

The accelerometer in the laptop senses the acceleration that the laptop is experiencing. When it is sitting on your desk, the accelerometer senses a constant 9.8 m/s^2 acceleration from the Earth's gravity. When it is in freefall, the accelerometer senses no acceleration, as you said. It is the sudden disappearance of the normal 9.8 m/s^2 gravitational acceleration that the laptop senses.

 

[Ranku]

The accelerometer in the laptop senses the acceleration that the laptop is experiencing. When it is sitting on your desk, the accelerometer senses a constant 9.8 m/s^2 acceleration from the Earth's gravity. When it is in freefall, the accelerometer senses no acceleration, as you said. It is the sudden disappearance of the normal 9.8 m/s^2 gravitational acceleration that the laptop senses.

Excellent answer!

 

[vanesch]

Meaning that you can't use this kind of laptop on a space flight...