n which of the following types of engine is the air-and-fuel mixture ignited by the heat created during the compression stage, rather than by a spark plug? A. An LP gas engine B. An electric engine C. A rotary engine D. A diesel engine

Many people believe that a vacuum created inside a vacuumcleaner causes particles of dirt to be drawn in. Actually, however, the dirt is pushed in. Explain.

For the reaction A + B → C + D, ΔH° = + 40 kJ and ΔS° = + 50 J/K. Therefore, the reaction under standard conditions is: A) spontaneous only at temperatures between 10 K and 800 K. B) spontaneous at temperatures greater than 800 K.

Mr. White claims that he invented a heat engine with a maximum efficiency of 90%. He measured the temperature of the hot reservoir as 100o C and that of cold reservoir as 10o C. Find the error that he made and calculate the correct efficiency.

If a box weighing 520 N is hung from a spring whose constant is 650 N/m, how many centimeters will the spring stretch?

Which of the following statements is/are true? Check all that apply. Check all that apply. The total mechanical energy of a system is constant only if all the forces doing work on it are nonconservative.

A gate in an irrigation canal is constructed in the form of a trapezoid 2 m wide at the bottom, 38 m wide at the top, and 2 m high. It is placed vertically in the canal so that the water just covers the gate.

A machine with a mechanical advantage of 10 is used to produce an output force of 250 newtons. What input force is applied to this machine

Why do you float in space

How does physical change affect the identity of a substance

A scientist pours grape juice on three identical white shirts He then uses three different cleaning products on the shirts and measures how clean they get what is the independent variable in this experiment