Which of the following statements is true about machines? a)- machines are structures made of one or more movable parts. b)- machines have a least one multiforce member as part. c)- machines transmit forces or alter the effect . d)- machines, unlike frames, can’t be constrained

Option c is True

Explanation:

a)- Machines are structures made of one or more movable parts. is false statement because Machines can be made without any movable part as in simple machines like inclined plains, wedges, screw etc.

b) Machines have a least one multi force member as part. is false statement since it is not a compulsory condition.

c) Machines transmit force or alter the effect. This is a true statement as machine are made in  the first place to transmit forces and alter the effect.  

d) Machines can be Contrained.

this is true

explanation:

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