8.) The Earth's magnetic poles remain in fixed positions, coinciding with the geographic poles. a. True b. False

2. A cosmic ray proton moving toward the Earth at 5.50×107 m/s experiences a magnetic force of 1.80×10-16 N. What is the strength of the magnetic field if there is a 41.0° angle between it and the proton’s velocity? (Is the value obtained for the field consistent with the known strength of the Earth’s magnetic field on its surface? Discuss.)   This is not and will not be graded

23. A 1000-kg car moves west along the equa- tor. At this location Earth's magnetic field is 3.5 × 10-5T and points north parallel to Earth's surface. If the car carries a charge of −2.0 × 10¯³ C, how fast must it move so that -3 the magnetic force balances 0.010% of Earth's gravitational force exerted on the car?

9. Two long parallel wires separated by 7.5 cm each carry 3.3 A in opposite directions. (µ0=4T x 10-7 T m/A) (a) What magnetic force per length acts on each of the wires? Is it attractive or repulsive? (b) Find the magnitude of the magnetic field midway between the two wires.

1. Two long, straight wires are parallel and 25 cm apart. (a) If each wire carries a current of 50 A in the same direction, what is the magnetic force per meter exerted on each wire? (b) Does the force pull the wires together or push them apart? (c) What happens if the currents flow in opposite directions?

3. Measurements of the magnetic field around a triangular path give the pattern shown in the figure. Determine the (net) conventional current (magnitude and direction) passing through the area defined by the triangle. 76-51 48-5 T 24 cm 25.3 cm 4c-5 T 7e-5 T (UDS 851

5. Find the expression for the magnetic field at point P in the wire configuration shown below. A current of 10 A flows along the wire shown. 40 cm 20 cm P Solution: B = -3.432 × 10-5 TÊ 20 cm

3. A proton, moving, North, enters a magnetic field. Because of this magnetic field the proton curves upward (out of the page). We may conclude that the magnetic field must have a component North West East South A) towards the west. B) towards the east. C) towards the south. D) towards the north. E) downward.

3. A proton moving eastward with a velocity of 5.0 km/s enters a magnetic field of 0.20 T pointing northward. What are the magnitude and direction of the force that the magnetic field exerts on the proton? (qe=+1.60 × 10-19 C)

8. A charge is moving at an angle of 30° relative to the direction of a magnetic field and experiences a magnetic force of 3.0 x 103 N. If this same charge were to move at the same velocity perpendicular to the same magnetic field what magnetic force will act on it? FL = qvB sint