A box of bananas weighing 51.0 N rests on a horizontal surface. The coefficient of static friction between the box and the surface is 0.46 and the coefficient of kinetic friction is 0.23. Part A If no horizontal force is applied to the box and the box is at rest, how large is the frictional force exerted on the box by the surface

static friction force = The coefficient of static friction * normal force

static friction force = 0.46 * 51 = 23.46 N

kinetic friction force = The coefficient of kinetic friction * normal force

kinetic friction force = 0.23 * 51 = 11.73 N

the applied force acting on the object must be more than 23.5 N if the object was stationary to move it and must be more than 11.7 N during the movement to keep the object moving

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