Why can't the efficiency of a heat engine be 100%?

I want to know which ball will get in more times if I throw it the same way 10 meters from the basketball hoop 10 times using three different balls: basketball, volleyball, or tennis ball. What is the independent variable in this experiment? A.

A 4kg mass traveling eastwards at 4m. s per second collides with a 3kg mass traveling westward as 8m. s per second ... calculate the total momentum of mass before they colide

How does acceleration of an object change in relation to its mass

Which elements will bond ionically with barium such that the formula would be written as BaX2? A) Nitrogen, chlorine, and sodium Eliminate B) Chlorine, iodine, and fluorine C) Hydrogen, bromine and aluminum D) oxygen and sulfur

The light ray is entering the water from the air. How should the light ray respond to the change of medium? A. It will slowdown and bend upward B. It will speed up and bend upward C. It will slow down and bend downward D.

Which friction-reducing technologies are used in the Variable Compression Turbo Engine?

A quadraphonic car stereo operates on electric current provided by the car's 12V battery and is connected in series. Each channel of the stereo, which feeds the electrical signal to one of the stereo's four speakers, has a resistance of 4.1 oums.

A cement block accidentally falls from rest from the ledge of a 15.0m high building. When the block is 14.0m above the ground, a man who is 1.71m tall looks up and notices that the block is directly above him.

a cricket ball is thrown vertically upward with an intial velocity of 4ms-1 find. a. Its velocity after three second. b. maximum height attained and the time taken to reach it

A student sees a newspaper ad for an apartment that has 1330 square feet of floor space how many square meters are there?