Answer:
Step-by-step explanation:
To find the magnitude of the charge on the van der Graff generator, you can use the formula for electric field due to a point charge:E=k∗∣q∣r2E=r2k∗∣q∣Where:EEis the electric field strength (given as 4.5×1054.5×105N/C).kkis the electrostatic constant (8.99×1098.99×109 N m²/C²).qqis the charge we want to find.rris the distance from the charge to the point where the electric field is measured (given as 0.75 meters).We can rearrange the formula to solve for qq:q=E∗r2kq=kE∗r2Now, plug in the values:q=(4.5×105 N/C)∗(0.75 m)28.99×109 N m²/C²q=8.99×109N m²/C²(4.5×105N/C)∗(0.75m)2Calculating this gives:q≈2.8×10−5 coulombsq≈2.8×10−5coulombsSo, the magnitude of the charge on the van der Graff generator is approximately 2.8 × 10⁻⁵ coulombs, which corresponds to option b.