Question

a) What is the relation between incline angle (0 degrees being flat, and 90 degrees being a vertical incline) and acceleration along the incline when friction is not involved?

g*(1-cos(theta)^2); g*sin(theta); g*(1-cos(theta)) or g*cos(theta)

b) When an object is on an incline, what is the relation between the objects weight and the normal force?

m*g*cos(theta); m*g*sin(theta); m*g*(1-cos(theta)) or m*g*(1-cos(theta)^2)

c) What is the force required to make an object under static friction begin motion?

a. the normal force times the coefficient of static friction

b. the normal force times the coefficient of kinetic friction

c. the force due to gravity times the coefficient of kinetic friction

d. mass times the coefficient of static friction

d) What is the relation between the coefficient of kinetic friction and the angle of inclination required to make an object have a constant velocity (no acceleration) going down an incline?

g*m*cos(theta); g*m*cos(theta) - N; tan(theta) or g*(1-cos(theta)^2)

e) The small angle approximation states that sin(theta) can be approximated as what when the angle, theta, is small?

theta in degrees; 1 - theta in radians; 1; or theta in radians

Answer 1

a) for mass on incline

mgsin = ma

a = gsin

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b) on an incline

N = mgcos

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c) the object will only move when applied force or net force is greater than maximum force of static friction,

so,

the normal force times the coefficient of static friction

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d) F_net = ma

as a = 0

F_net = 0

mgsin - u_kmgcos = 0

sin = u_kcos

u_k = sin / cos

u_k = tan

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e) not sure about this one, but I think  theta must be in radians