Advertisements
Advertisements
प्रश्न
The diagram below shows a pulley arrangement.
(i) In the diagram, mark the direction of the forces due to tension, acting on the pulley P.
(ii) What is the purpose of the pulley Q?
(iii) If the tension is T newton, deduce the relation between T and E.
(iv) Calculate the velocity ratio of the arrangement.
(v) Assuming that the efficiency of the system is 100%, what is the mechanical advantage?
(vi) Calculate the value of E
उत्तर
(ii) The purpose of the pulley Q is to change the direction of application of effort to a convenient direction.
(iii) In the diagram, T = E
(iv) If the free end of the string moves, through the distance x, the load will rise by a distance x/2.
Threfore, V.R = distance moved y the effort arm / distance moved by the load = `"x"/("x"//2) = 2`
(v) In equilibrium,L = 2T and E = T
efficiency = M.A / V. R
or, 1 = `("M ""A")/2`
⇒ M.A = 2
(vi) M.A = `"L"/"E"`
⇒ E = `"L"/("M"."A") = 100/2` = 50 N
APPEARS IN
संबंधित प्रश्न
Rohan exerts a pull of 150 kgf. What is the maximum load he can raise with this pulley system if its efficiency = 75%?
State two functions of a machine.
State if the following statement is true or false. Correct the statement if it is false.
A single movable pulley is a pulley that has its axis of rotation fixed.
Define the following term in reference to a gear system for Gain in speed ?
Name the type of single pulley that can act as a force multiplier. Draw a labelled diagram of the pulley mentioned by you.
Give reason for the following:
The lower block of a block and tackle pulley system must be of negligible weight
A type of single pulley is very often used as a machine even though it does not give any gain in mechanical advantage. Name the type of pulley used.
A type of single pulley is very often used as a machine even though it does not give any gain in mechanical advantage. For what purpose is such a pulley used?
In the alongside the figure of two pulleys shown a system in which one pulley is fixed and the other is movable. What is the velocity ratio of the system?
An effort of 600 N is needed to lift a weight of 1000 N. What are the mechanical advantage and efficiency of the pulley system?
Complete the table.
| S. No | Types of Simple Machine | Example |
| 1. | Pulley | |
| 2. | Wheel and axle | |
| 3. | Wedge | |
| 4. | Inclined plan | |
| 5. | Lever | |
| 6. | Screw |
