Why is the efficiency of a machine always less than 100 percent

A wave has a wavelength of 9 mm and a frequency of 18 hertz. What is its speed?

A (n) a0 is software that contains rows and columns used to make calculations, organize information, and make comparisons.

A bar magnet is a dipolar. This means is has how many poles

Would ice be considered a fluid or solid?

When light passes from one medium to another, resulting in a change in speed and direction of insolation,?

Which of these is the best reason for proper nutrition? A. To ensure that you will be skinny B. To protect yourself against certain diseases C. To improve your intelligence D. To ensure that you will get good grades

And object has a mass of 15g it has a volume of 7.5ml. find the density of the object.

I need this answered quickly. is the branch of science for naming and classifying organisms based on their natural relationships? A-physics B-taxonomy C-genetics D-biology

For a fixed amount of gas, if the absolute temperature of the gas is doubled, what happens to the pressure of the gas?

A 500-kilogram sports car accelerates uni- formly from rest, reaching a speed of 30 me- ters per second in 6 seconds. What distance has the car traveled during the 6 seconds?