A copper strip 20cm wide and 1.5mm thick is placed in a magnetic field of 1.75wbm^2.if a current of 220A is set up in the strip,what hall potential difference appears across the strip?(n=8.5×10^28m^2 and e=1.6×10^-19)?

Yes

To find the Hall potential difference across the copper strip, we need to use the formula:

Hall Voltage (VH) = (B * I * d) / (n * e)

where:
- B is the magnetic field strength in Tesla (T),
- I is the current flowing through the strip in Amperes (A),
- d is the thickness of the strip in meters (m),
- n is the charge carrier density in inverse square meters (m^-2),
- e is the elementary charge in Coulombs (C).

First, let's convert the given dimensions into SI units:

Width of the strip (w) = 20 cm = 0.2 m
Thickness of the strip (d) = 1.5 mm = 0.0015 m

Now we can substitute the values into the formula:

VH = (B * I * d) / (n * e)

The magnetic field strength (B) is given as 1.75 wbm^2. However, we need to convert it to Tesla (T) by dividing by 10000:

B = 1.75 wbm^2 / 10000 = 0.000175 T

Next, substitute the values we have:

VH = (0.000175 T * 220 A * 0.0015 m) / (8.5 × 10^28 m^-2 * 1.6 × 10^-19 C)

Now, calculate the Hall potential difference:

VH = (0.00004095) / (13.6)
≈ 0.003011 V

Therefore, the Hall potential difference across the copper strip is approximately 0.003011 V or 3.011 mV.