Answer:
No.b answer
the ratio of the length of the lever arm where the force is applied divided by the length of the lever are that lifts the load.
No.1 answer
if there is no friction in a simple machine, work output and work input are found to be equal in the machine.
No.3 answer
machine that is 75% efficient means that 75% of the work input is obtained as the useful output and the remaining 25% has been lost in overcoming the friction.
No.4 Answer
A lever is a simple machine made of a rigid beam and a fulcrum. In 3 calss lever is classified.
Simple pulleys change the direction of the force used to lift an object over a distance.
ratio of distance travelled by effort to the distance travelled by load in the machine.
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