What causes the tidal forces on Earth?

The tidal forces on Earth are primarily caused by the gravitational pull exerted by the Sun and the Moon on our planet. These celestial bodies have strong gravitational fields, and as they exert this force, they create variations in gravitational attraction across different areas on Earth.

For instance, the side of Earth that is closest to the Moon experiences stronger gravitational pull compared to the side that is farthest away. This difference in gravitational force leads to the formation of bulges of water—essentially high tides—on the side facing the Moon. Similarly, there are also tidal effects caused by the Sun, but its influence is less pronounced than that of the Moon due to its greater distance from Earth.

The factors responsible for tidal forces must be understood in the context of their gravitational nature. While Earth's rotation contributes to the phenomenon of tides and can modify the timing of tide cycles, it is the gravitational pull from the Moon and the Sun that fundamentally creates the tidal forces we observe. Other options like Earth's magnetic field and atmospheric pressure do not play a role in the creation of tidal forces, as they do not exert a significant gravitational influence on ocean waters.

Therefore, the primary cause of tidal forces is indeed the gravity from the Sun and Moon.