Net force acting on the car is 3 x 10^3 Newtons:
Answer:
The answer is below
Explanation:
The average resistivity of the human body (apart from surface resistance of the skin) is about 5.0 Ωm. The conducting path between the right and left hands can be approximated as cylinder 1.6 m long and 0.10 m in diameter. The skin resistance can be made negligible by soaking the hands in salt water. (a) What is the resistance between the hands if the skin resistance is negligible? (b) if skin resistance is negligible, what potential difference between the hands is needed for lethal shock current 100 mA?
Solution:
The resistance (R) of a material is given by the formula:
R = ρL / A
where L is the length of the conductor, ρ is resistivity and A is the cross sectional area.
a) R = ρL / A
ρ = 5.0 Ωm, L = 1.6 m, A = π(diameter²) / 4 = π(0.1²)/4 = 0.00785 m²
R = 5(1.6) / 0.00785 = 1018.6 ohm
b) To produce 100 mA, we need to use ohms law:
I = 100 mA = 0.1 A, R = 1018.6 ohm
V = IR = 0.1(1018.6)
V = 101.86 V
I believe the answer is 3 Newtons!
