Gobezoch › Textbooks › Physics Grade 9
Physics Grade 9 Unit 5: Simple Machines
national exam questions have come from this unit. It runs 34 pages; one careful study pass takes about 2.4 hours, and its difficulty is easier among Physics units. Each section below lists the questions set from it, with the year, and opens the page that teaches it.
5.1 Simple Machines and their Purposes · read p. 86
Not asked in a national paper yet.
5.2 Simple Machines at Home · read p. 89
Not asked in a national paper yet.
5.3 Simple Machines at Work Place · read p. 91
Not asked in a national paper yet.
5.4 Classification of Simple Machines · read p. 93
Not asked in a national paper yet.
5.5 Mechanical Advantage, Velocity Ratio and Efficiency of Simple Machine · read p. 96
- 2018 E.C., Q12 – The efficiency of a simple machine is defined as the ratio between:
- 2018 E.C., Q14 – Which one of the following statements is correct about simple machines?
- 2017 E.C., Q2 – A force that is exerted on a simple machine in order to produce input work is called
- 2015 E.C., Q26 – An inclined plane is 20 m long and is inclined at an angle of 15° to the horizontal. If the effort required to push a block of weight 3,000 N up the slope is 900 N, what is the efficiency of the inclined plane?
5.6 Designing Simple Machine · read p. 113
- 2017 E.C., Q5 – m A force is used to push a box of mass, along the slope of an inclined plane with constant velocity. If the μ coefficient of friction between the box and the inclined plane be , the actual mechanical advantage (AMA) of
- 2017 E.C., Q6 – A wheel and axle of radii 40 cm and 8 cm, respectively, is used to lift a bucket of 6 kg of water from a well by applying an effort of 20 N on the wheel. The percentage efficiency of this simple machine is
- 2016 E.C., Q27 – A farmer pulls out a bucket of water from a well with wheel and axle with radii of 30 cm and 6 cm respectively. Assuming no energy losses, what effort should be applied on the wheel in order to lift a load of 40 N on the