Iron's ability to rust is not a physical property because

a. it cannot be observed.

b. the identity of iron stays the same.

c. a new substance with new properties is formed.

d. iron is magnetic

Ablock having mass m slides down an inclined plane. the force of friction between the block and the inclined plane is f, the block's weight is m g, and the normal force is n. (a) draw a free – body force diagram showing the forces acting on the block. (b) write down all relevant newton’s equations for a given situation.