A box weighing 30 N is on a horizontal floor. The coefficient of static friction is 0.30 and that of kinetic friction is 0.25. Find the frictional force under the following conditions: a) no additional forced is added, b) a force of 5 N is applied to the east, c) a force of 9 N is applied to the west, d) a force of 10 N is applied to the south.

Which of the following are properties of mechanical waves? check all that apply ⭕️ particles of the medium move back and fourth, but do not move with the wave. ⭕️ the particles of the medium always move parallel to the wave motion. ⭕️ wave motion begins with a disturbance in the medium. ⭕️ waves transport energy from a source outward, away from the source.

The boy of mass 30 kg is at r1= 2 meters from the fulcrum. of the girl is 45 kg, at what r2 must she sit so that they are balanced ?

Properties seen when one one substance changes to another are known as properties