Can the earth’s magnetic field be vertical at a place? What will happen to a freely suspended magnet at such a place? What is the value of dip here?
Yes, The magnetic field of the earth is vertical at poles. So, a freely suspended magnet will try to align with earth’s magnetic field. Hence the magnet will stay in a vertical position, with its south pole pointing towards Earth’s south pole, which is magnetic north.
As angle of dip is the inclination between the horizontal and the magnetic field lines of earth, poles will have an angle of dip of value 90°