A box weighing 100 newtons is pushed up an inclined plane that is 5 meters long. It takes a force of 75 newtons to push it to the top,which has a height of 3 meters. What is the efficiency?

7 answers

100x3=300 75x5=375

300/375=.80 or 80%

Divide the potential energy change (100 N x 3 m)) by the work done (75 x 5 J).

Why do we cross multiply. I though you multiply 100 x 5 then 75 x 5 and then divide and multiply by 100

45 100*5=500

75*3=225
500/225=2.22recurring

the formula for potential energy is mass * acceleration of gravity* height. not mass * height

65

Did you know?

Did you know that efficiency in physics is a measure of how well a machine or system converts input energy into useful work output? In the scenario provided, where a box weighing 100 newtons is pushed up a 5-meter long inclined plane with a force of 75 newtons to reach a height of 3 meters, the efficiency can be calculated. The efficiency is determined by dividing the useful work output by the total input energy. Here, the useful work output is the weight of the box multiplied by the height it is lifted (100 N x 3 m = 300 Nm), and the total input energy is the force applied to push it multiplied by the distance over which it is pushed (75 N x 5 m = 375 Nm). Therefore, the efficiency is given by (300 Nm / 375 Nm) x 100 = 80%. This means that the system is 80% efficient in converting the input energy into useful work output.