Mechanics: Kinetic Friction

UNIVERSITI TUNKU ABDUL RAHMAN Centre
Course
Year/ Trimester
Session
: Centre for Foundation Studies (CFS)
: Foundation in Science
: Year 1 / Trimester 1
: 201401
Unit Code
Unit Title

: FHSC1014
: Mechanics

Tutorial 4: Application of Newton’s Laws.

1. The distance between two telephone poles is 50.0 m. When a 1.00 kg bird lands on the telephone wire midway between the poles, the wire sags 0.200 m. Draw a free-body diagram of the bird. How much tension does the bird produce in the wire? Ignore the weight of the wire. [614 N]

2. A 40 kg crate rests on a horizontal floor, and a 75 kg person is standing on the crate. Determine the magnitude of the normal force that (a) the floor exerts on the crate and (b) the crate exerts on the person. [(a) 1.13 x 103 N, (b) 735 N]

3. A worker stands still on a roof sloped at an angle of 45° above the horizontal. He is prevented from slipping by a static frictional force of 450 N. Find the mass of the worker. [85 kg]

4. A 4.0-kg bucket of water is raised from a well by a rope. If the upward