Answer:
true?
Explanation:
Im positive but not 100% sure wait for someone else to answer and see if they say the same.
Answer: A. Work is done on the system and heat is transferred from the system for a net decrease in internal energy.
Explanation:
A refrigerator is a device which dispenses heat from the close system to a warmer area or in the surrounding. By dispensing the heat the internal temperature of the refrigerator drops. The system of refrigerator violates the second law of thermodynamics. As it performs the work to cool the region instead of heating the region. The work is done on the system and the internal energy decreases and the heat energy is liberated to the surrounding area. A refrigerator is an open system.
Answer:
and 
Explanation:
The wavelength of a visible light is 727.3 nm.

The formula is as follows :

f is the frequency of the visible light

Energy of a photon is given by :
E = hf, h is Planck's constant

Red color has a frequency of
and energy per photon is
.
Answer:
Please check the explanation.
Explanation:
The slope of the velocity-time graph illustrates the change in velocity with respect to change in time.
In other words, the acceleration of the object is defined by the slope of a velocity graph. The acceleration can be obtained by finding the slope at a particular time.
Hence, the slope of the velocity time graph represent represents acceleration.
2. Also the acceleration of any object, like a car or bike, at some discrete instant in time 't' is termed as instantaneous acceleration which can be determined if we may take the derivate of the given velocity function.
3. A vector that has a direction and magnitude of 1 is termed as a unit vector, often called a direction vector.