A pinecone with a mass of 300 g starts from rest and slides down along a roof that is inclined at 30 from the horizontal. After sliding 7 m, the pinecone falls off the edge of the roof from a height of 5 m above the ground. The coefficient of kinetic friction between the pinecone and the roof is 0.15.

a) Draw and label a free-body diagram of the pinecone while it is sliding along the roof. (1)

b) How fast is the pinecone moving at the instant that it falls off the roof? (4)

c) How far horizontally does the pinecone travel from the instant it leaves the roof to the instant that it

strikes the ground? (5)