Yes, the Earth is constantly in motion. It rotates on its axis, completing one full rotation in approximately 24 hours, resulting in day and night cycles. Additionally, the Earth orbits around the Sun, completing one orbit in about 365.25 days, giving us the concept of a year.
However, we typically don't feel the Earth's motion because it is a gradual and continuous process. Just like when you are inside a moving vehicle, you don't always feel the motion unless there are sudden changes or external forces acting upon you.
Our perception of motion is relative to our surroundings. Since we are also part of the Earth and its atmosphere, we are moving along with it at the same speed. Therefore, we don't feel the Earth's rotation or orbital motion in our day-to-day experiences.
The absence of noticeable sensations of motion can also be attributed to the Earth's size and the smoothness of its motion. The Earth's rotation and orbital speed are relatively constant and do not cause drastic accelerations or decelerations that would be easily perceptible to us.
However, even though we don't feel the Earth's motion directly, its effects are observable. The changing positions of celestial bodies, such as the Sun's apparent movement across the sky or the positions of stars at night, provide evidence of the Earth's rotation and its orbit around the Sun.