The diagram below is a t positive x direction. The second child exerts a force o
ID: 1780020 • Letter: T
Question
The diagram below is a t positive x direction. The second child exerts a force of F'. 8 N at an angle 2 = 30° dockwise from the positive x direction. view of two children pulling a 11.7-kg sled along the snow. The first child exerts a force of F1-1311 at an angle . = 45 (a) Find the magnitude and direction of the friction force acting on the sled if it moves with constant velocity 15 6 Did you What is the acceleration for an object moving with constant velocity? N counterclockwise from the +x-axis (b) What is the coefficient of kinetic friction between the sled and the ground? 136 What is the relationshi 45Explanation / Answer
here,
F1 = 13 * ( cos(theta1) i + sin(theta1) j) N
F1 = 9.19 i N + 9.19 j N
F2 = 8 * ( cos(theta2) i - sin(theta2) j)
F2 = 7.01 i N - 4 j N
net force , F = F1 + F2
F = 16.2 i N + 5.19 j N
a)
as the sled is moving at constant speed,
the net force is zero
ff = - F = - 16.2 i N - 5.19 j N
the magnitude of frictional force , |ff| = sqrt(16.12^2 + 5.19^2) N
|ff| = 17 N
theta = arctan(-16.2 /(-5.19))
theta = 199.5 degree counterclockwise from +x axis
b)
let the coefficient of kinetic friction be uk
uk* M * g = ff
uk * 11.7 * 9.8 = 17
uk = 0.15