Question

A 1000-kg car pulls a boat on a trailer. (a) What is the magnitude of the total force that resists the motion of the car, boat, and trailer, if the car exerts a 2100-N force on the road and produces an acceleration of 0.428 ?/?2? The mass of the boat plus trailer is 666 kg.

(b) What is the magnitude of the force in the hitch between the car and the trailer if 80% of the resisting forces are experienced by the boat and trailer?

Answer 1

here,

mass of car , m1 = 1000 kg

mass of boat and trailer ,m2 = 666 kg

let the magnitude of the total resistive force be Fr

using Newton's second law

(m1 + m2) * a = (Fapplied - Fr)

(1000 + 666) * 0.428 = ( 2100 - Fr)

solving for Fr

Fr = 1387 N

the magnitude of the total resistive force is 1387 N

b)

the resistive force on the boat and trailer , Fr' = (80/100) * Fr

Fr' = 0.8 * 1387 N = 1109.6 N

the magnitude of force in the hitch , F = Fr' + m2 * a

F = 1109.6 + 666 * 0.428 N

F = 1394.6 N