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प्रश्न
The following belong to which class of lever?
A pair of scissors
To which class of lever does a pair of scissors belong?
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उत्तर
The pair of scissors belongs to a Class I lever.
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संबंधित प्रश्न
Name a machine to obtain gain in speed?
State the principle of a lever?
The lever for which the mechanical advantage is less than 1 has :
A 4 m long rod of negligible weight is to be balanced about a point 125 cm from one end and a load of 18 kgf is suspended at a point 60 cm from the support on the shorter arm.
- If a weight W is placed at a distance of 250 cm from the support on the longer arm to balance the rod, find W.
- If a weight 5 kgf is kept to balance the rod, find its position.
- To which class of lever does it belong?
A 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.
- Draw a diagram of the arrangement showing the fulcrum (F), load (L) and effort (E) with their directions.
- State the kind of lever.
- Calculate:
- load arm,
- effort arm,
- mechanical advantage and
- the effort needed.
Fig 3.17 below shows a lever in use.
(a) To which class of lever does it belong?
(b) If FA = 80 cm, AB = 20 cm, find its mechanical advantage.
(c) Calculate the value of E.
Which class of lever found in the human body is being used by a boy when he raises the weight of his body on his toes?
Shears, used for cutting metals and scissors used for cutting clothes are both examples of levers of the first order. However, whereas the shears always have short blades and long handles, the scissors often have blades much longer than the handles. Explain, why this is so?
The diagram shows the use of a lever.
- State the principle of moments as applied to the above lever.
- Which class of lever is this? Give an example of this class of lever.
- If FA = 100 cm, AB = 90 cm, calculate the minimum effort required to lift the load.
What is a first-order lever?
