Question about Newton's Laws Experiment

Question

If I make an entire experiment about Newton's first laws that was performed on a train traveling at a constant speed, would my recorded data change and why or why not?

Answer 1

If you are at home performing the experiment, would you see any anomalies associated with movement? And yet the earth is spinning at 1000 miles per hour and traveling around the sun at 67,000 miles per hour and you have no perception of that happening.

If you closed the curtains on the train, could you tell it was moving (assuming its a smooth ride)?

Answer 2

I love William's answer. It all comes down to the fact that, at a constant velocity, you and your experiment are not moving relative to the train. There is no extra acceleration to add or subtract, An observer standing still on the ground outside the train would see the velocity of the train added to the motion you observe.