85.5 applications of Newton's law Solution: mg cosa ma d mg cos ads= m-ds=mdu ds=la、ds∠U g cos ada=UdU g cos ada= Udu U=√2 gluing T-mgsin6=ma=m = 3mg sin 0 85.5 applications of Newtons law Example 3: a block of mass m is placed on a frictionless inclined plane of a triangle block of mass M which is on the frictionless horizontal plane, the inclined plane is at the angle 0 to the horizontal Find(a)the magnitude of the norma force of the inclined plane on the block; (b)the acceleration of m with respect to M.14 t mg ma m d d cos υ α = τ = υ υ α d d d d d d cos d t s s m t mg s = m = = α =υ t s s l d d d d , g cosαdα = υdυ l T mg man m 2 sin υθ − θ = = Solution: Tθ = 3mg sin θ υθ = 2glsinθ ∫ ∫ = θ υθ α α υ υ 0 0 g cos d d §5.5 applications of Newton’s law O l θ T r mg r α v r ds dα M θ m Example 3: A block of mass m is placed on a frictionless inclined plane of a triangle block of mass M which is on the frictionless horizontal plane , the inclined plane is at the angle θ to the horizontal. Find (a)the magnitude of the normal force of the inclined plane on the block;(b)the acceleration of m with respect to M. §5.5 applications of Newton’s law