19 solutions available
Question 1Derive a relationship between mechanical advantage, velocity ratio and efficiency of a machine.
Question 5A man uses a crowbar of length 1.5 m to raise a load of 75 kgf by putting a sharp edge below the bar at a distance 1 m from his hand.(a)...
Question 6A pair of scissors is used to cut a piece of cloth by keeping it at a distance of 8.0 cm from its rivet and applying an effort of 10 kgf by...
Question 11Ramesh went for fishing with his fishing rod. Identify the class of lever for a fishing rod. If a fish exerts a load of 10 N and the...
Question 13A fire tongs has its arms 20 cm long. It is used to lift a coal of weight 1.5 kgf by applying an effort at a distance 15 cm from the...
Question 14The diagram below shows a rod lifting a stone.(a) Mark position of fulcrum F and draw arrows to show the directions of load L and effort...
Question 15State the kind of lever which always has the mechanical advantage less than 1. Draw a labelled diagram of such a lever.
Question 16Explain why mechanical mechanical advantage of class III lever is always less than 1.
Question 17Classes III levers have mechanical advantage less than 1. Why are they then used?
Question 18State the class of levers and the relative positions of load (L), effort (E) and fulcrum (F) in(a) a bottle opener, and(b) sugar tongs.
Question 19Indicate the positions of load L, effort E and fulcrum F in the forearm shown below. Name the class of lever.
Question 7Draw a diagram of combination of three movable pulleys and one fixed pulley to lift up a load. In the diagram, show the directions of load,...
Question 9A boy uses a single fixed pulley to lift a load of 50 kgf to some height. Another boy uses a single movable pulley to lift the same load to...
Question 12For a system of n pulleys, the weight of the lower block along with pulleys is w, then its efficiency is given by:η=1−wnE\eta = 1 -...
Question 2A fixed pulley is driven by a 100 kg mass falling at a rate of 8.0 m in 4.0 s. It lifts a load of 75.0 kgf.Calculate —(a) The power input...
Question 3A single fixed pulley and a movable pulley both are separately used to lift a load of 50 kgf to the same height. Compare the efforts...
Question 4In a block and tackle system consisting of 3 pulleys, a load of 75 kgf is raised with an effort of 25 kgf.Find —(i) the mechanical...
Question 8Figure shows a system of four pulleys. The upper two pulleys are fixed and the lower two are movable.(a) Draw a string around the pulleys....
Question 10A block and tackle system has the velocity ratio 3. Draw a labelled diagram of the system indicating the points of application and the...