Answer: work must be done on the system (Option A)
Explanation:
The second law of thermodynamics is the fundamental law of nature; it states that energy can be transferred from cold objects to hot objects only, if work is done on the system. If energy is added to the system then as a result the thermal energy would increase. Second law of thermodynamics is used to determine whether a process is spontaneous or not. Moreover,the second law of thermodynamics is also used in refrigerators.
Answer:
d. 37 °C
Explanation:
= mass of lump of metal = 250 g
= specific heat of lump of metal = 0.25 cal/g°C
= Initial temperature of lump of metal = 70 °C
= mass of water = 75 g
= specific heat of water = 1 cal/g°C
= Initial temperature of water = 20 °C
= mass of calorimeter = 500 g
= specific heat of calorimeter = 0.10 cal/g°C
= Initial temperature of calorimeter = 20 °C
= Final equilibrium temperature
Using conservation of heat
Heat lost by lump of metal = heat gained by water + heat gained by calorimeter
When an ion is formed, the number of protons does not change. ... By removing an electron from this atom we get a positively charged Na+ ionthat has a net charge of +1. Atoms that gain extra electrons become negatively charged. A neutral chlorine atom, for example, contains 17 protons and 17 electrons.
Answer:
30 Watts
Explanation:
Power = Work/Time
Work = Force*Distance
Power = Force * Distance / Time
Power = 15 N * 20 meters / 10 sec
Power = 30 Watts
It is a mechanical wave and cannot travel through a vacuum.
