The output work of a machine compared to the input work is the efficiency of the machine.

True

Explanation:

Efficiency of machine is determined by dividing the work output by the work input and normally expressed as a percentage hence the above statement is true. Normally, the efficiency of a machine is not always 100% due to energy losses within machine parts. The energy losses are mainly attributed to friction hence methods of reducing friction within mechanical parts such as oiling and greasing are recommended to achieve higher mechanical efficiency.

from 1609, galileo galilei used the recently invented telescope to observe the sun, moon and planets. he saw the mountains and craters of the moon, and for the first time revealed the planets to be worlds in their own right. galileo also provided strong observational evidence that planets orbited the sun.

his discoveries about the moon, jupiter's moons, venus, and sunspots supported the idea that the sun - not the earth - was the center of the universe, as was commonly believed at the time.galileo turned his gaze toward venus, the brightest celestial object in the sky - other than the sun and the moon.

if they have a finite resultant