What are limits of earth's magnetic field?

What is magnetic field?

Define the elelemts of the earth's magnetic field.

Write about earth's magnetic field.

Write the value of earth's magnetic field.

A wheel with 25 metallic spokes each 0.4m long is rotated with a speed of 150 rev//min in a plane normal to the horizontal components of earth's magnetic field H_B at a place. If H_E=0.4G at the place, what is the induced emf between the axle and the rim of the wheel?

Where is the vertical component of earth's magnetic field zero?

The dip at a place is (30^0) and If the vertical component of earth's magnetic field at that point is 7.5×10^−5 T. then what will be the total magnetic field of earth at that point.

"The strength of the earth's magnetic field varies from place to place". Explain.

Find the value of the vertical component and resultant intensity of the earth's magnetic field at a place where H is 0.2 G and angle of dip is 60°.