If the work put into a lever is 930 joules and the work accomplished is 870 joules, the efficiency of the lever is
107%
100%
94%
60%

♥ C) 94%
♥ If the work put into a lever is 930 joules and the work accomplished is 870 joules, the efficiency of the lever is 94%.
♥ 870/930=93.5
♥ And rounded you get 94.

The correct answer to this question is C) 94%.

CALCULATION:

As per the question, the work put into a lever is 930 Joule.

Hence, input work W = 930 Joule.

Work accomplished by the lever is 870 Joule.

Hence, the output work W' = 870 Joule.

We are asked to calculate the efficiency of the level.

The efficiency of the lever is defined as the ratio of output work to the input work.

Mathematically efficiency

                                               

                                                 

       In percentage, efficiency

                                                 

                                                                    [ans]

Hence, the efficiency of the lever is 94%.

False. conservation of momentum means that the momentum before and after any collision is always the same. this is the case even for things like explosions (which are actually a type of collision) as if you worked out the momentum of each piece of an object after the object exploded and added them all together, it would be the same as the momentum of the object originally.