A weight lifter is trying to do a bicep curl with a weight of 300 N. At the "sticking point", the moment arm of this weight is 30 cm about the elbow axis of rotation. The maximum force that the elbow flexor muscles can create for this situation is 4000 N and the moment arm of the elbow flexors is 2 cm. Can the lifter get past this sticking point?

Air enters a gas turbine with two stages of compression and two stages of expansion at 100 kpa and 17°c. this system uses a regenerator as well as reheating and intercooling – the intercooler returns the air to the inlet temperature. the pressure ratio across each compressor is 4 ; 300 kj/kg of heat are added to the air in each combustion chamber; and the regenerator operates perfectly while increasing the temperature of the cold air by 20°c. determine the system’s thermal efficiency. assume isentropic operations for all compressor and the turbine stages and use constant specific heats at room temperature. (0.378)

By what primary heat transfer mechanism does the sun warm the earth?

Ateacher gives students four liquids commonly found in the kitchen - vinegar, apple juice, dish detergent, and milk - and ph indicator strips, which measure acidity. the teacher asks the students to put the liquids in order from most acidic to most basic. what type of investigation could the students conduct to determine the correct order for the liquids?