Near San Francisco, where the vertically downward component of the earth's magnetic field is 6.8 x 10-5 T, a car is traveling forward at 17 m/s. The width of the car is 2.1 m. Find the emf induced between the two sides of the car. If positive charge accumulates on the driver's side, the enter the emf as a positive number. If negative charge accumulates on the driver's side, the enter the emf as a negative number

To find the emf (electromotive force) induced between the two sides of the car, we will use the formula:

emf = B * L * v

where:
B is the strength of the magnetic field (in Tesla),
L is the length of the conductor (in this case, the width of the car),
v is the velocity of the conductor (the car in this case).

Given:
B = 6.8 x 10-5 T (strength of the magnetic field)
L = 2.1 m (width of the car)
v = 17 m/s (velocity of the car)

Let's substitute these values into the formula:

emf = (6.8 x 10-5 T) * (2.1 m) * (17 m/s)

Calculating this expression, we find the following:

emf = 2.786 x 10-3 V

The emf induced between the two sides of the car is 2.786 x 10-3 volts. Since positive charge accumulates on the driver's side, the emf will be a positive value.