Accelerometer and Freely Falling Objects?

Question

I am building a device to put in a model rocket. This device will read acceleration and from that i will derive velocity and other information.

The device contains an accelerometer. This is my question.

On motor startup i know the accelerometer will register something because of the force from the pushing upwards and gravity pushing downwards.

After motor burnout and the rocket is still flying up (free falling) what exactly will the accelerometer read?

Does it read nothing after burnout of the motor or does it read drag forces?

Someone elaborate please.

Answer 1

An accelerometer should read the net acceleration of the rocket.  When it is in free fall, it should measure the acceleration of the rocket, which is a combination of gravity and drag.  It won't give the value of each force, but it should give the resultant acceleration.