|Centre |: Centre for Foundation Studies (CFS) |Unit Code |: FHSC1014 |
|Course |: Foundation in Science |Unit Title |: Mechanics |
|Year/ Trimester |: Year 1 / Trimester 1 | | |
|Session |: 201401 | | |
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 acceleration of the bucket is 5.0 m/s2, find the force exerted by the rope on the bucket. [59 N]
5. A block is pressed against a vertical wall by a force [pic], as the drawing shows. This force can either push the block upward at a constant velocity or allow it to slide downward at a constant velocity. The magnitude of the force is different in the two cases, while the directional angle ( is the same. Kinetic friction exists
