CP A proton is placed in a uniform electric field of 2.75 X 103 N/C. Calculate (a) the magnitude of the electric force felt by the proton; (b) the proton’s acceleration; (c) the proton’s speed after 1.00 µs in the field, assuming it starts from rest.
Solution 25E Introduction We first have to calculate the force on the proton in the uniform magnetic field. Then we have to calculate the acceleration and then we have to calculate the speed of the proton after 10 µs. Step 1: The force on the proton on an electric field E is given by F = eE Here e = 1.6 × 10 19 C is the charge of the proton and E = 2.75 × 10 N/C is the strength of the electric field. Hence the force on the proton is given by 19 3 16 F = (1.6 × 10 C)(2.75 × 10 N/C) = 4.4 × 10 N Step 2: The mass of the proton is m = 1.67 × 10 27 kg , hence the acceleration of the proton in the field is F 4.4×1016N 11 2 a = m = 1.67×102kg = 2.63 × 10 m/s