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प्रश्न
A pulley system has a velocity ratio 3. Draw a diagram showing the point of application and direction of load (L), effort (E) and tension (T). It lifts a load of 150 N by an effort of 60 N. Calculate its mechanical advantage. Is the pulley system ideal? Give reason.
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उत्तर
Given,
Effort = 60 N
Load = 150 N
As we know,
M.A. = `"Load"/"Effort"`
Substituting the values in the formula for M.A. we get,
= `150/60`
= 2.5 N
Therefore, Mechanical advantage = 2.5
संबंधित प्रश्न
State whether the following statement is True or False.
A pulley changes the direction of force.
What is a pulley?
What is the mechanical advantage of an ideal pulley?
Differentiate between a single fixed pulley and a single movable pulley.
Solve the following numerical problem.
What effort will be required to lift a load of 500 N by a single movable pulley? [Hint: Mechanical advantage of a single movable pulley is two].
Explain how a gear system can be used to obtain Change in direction of rotation. Given one example.
What is a block and tackle system of pulleys?
Fig shown a block and tackles system of pulleys used to lift a load.
(i) How many strands of tackle are supporting the load?
(ii) Draw arrows to represent tension in each stand.
(iii) What is the mechanical advantage of the system?
(iv) When load is pulled up by a distance 1 m how far does the effort end move?
(a) Fig represents an incomplete diagram of a simple string pulley system. Copy this diagram on a new page and complete it and mark where the effort must be applied to lift the load.
(b) What is the velocity ratio of this system?
(c) If the pulley system is 80% efficient and the load is 720 N, then
(i) What effort must be applied to lift the load?
(ii) What work must be done must be done in lifting the load through a distance of 2 m using this machine?
| Meera chose to use a block and tackle system of '9' pulleys instead of a single movable pulley to lift a heavy load. |
Why should she connect more number of pulleys in the upper fixed block?
