A force F = (cx-3.00x2) i acts on a particle as the particle moves along an x axis, with F in newtons, x in meters, and c a constant. At x = 0 m, the particle's kinetic energy is 18 J; at x = 5 m, it is 12 J. Find c.

Question

Physics

Anabella Pruitt

8 October, 19:52

A force F = (cx-3.00x2) i acts on a particle as the particle moves along an x axis, with F in newtons, x in meters, and c a constant. At x = 0 m, the particle's kinetic energy is 18 J; at x = 5 m, it is 12 J. Find c.

+5

Answers (1)

Know the Answer?

Elaine Adkins · Answer 1

The value of c is 9.52

Explanation:

Given;

force F = (cx-3x²) i which act on the particle through a distance x

The kinetic of the particle = Fdx

given Kinetic energy as 18 J

KE = ∫Fdx

KE = ∫ (cx-3x²) dx

KE = ¹/₂cx² - ¹/₃ (3x³) + k

KE = ¹/₂cx² - x³ + k

where, k is the constant of integration

Given at x = 0 m, KE = 18 J, substitute in this in the integral equation

18 = ¹/₂c (0) ² - (0) ³ + k

k = 18

Also, Given at x = 5 m, KE = 12 J substitute in this as well in the integral equation;

12 = ¹/₂c (5) ² - (5) ³ + 18

12 = 12.5c - 125 + 18

12.5c = 12 + 125 - 18

12.5c = 119

c = 119/12.5

c = 9.52