Answer:
35°
Explanation:
By laws of reflection,
Angle of incidence = Angle of reflection
Angle between incident ray and reflected ray = 70°
Angle of incidence + Angle of reflection = 70°
Since,
Angle of incidence = Angle of reflection
Angle of incidence + Angle of incidence = 70°
2 Angle of incidence = 70°
Divide 2 on both sides,
Angle of incidence = 70° / 2
Angle of incidence = 35°
Answer:
According to II law of thermodynamics the heat always transfers from high temperature to low temperature body without aid of any external energy. So, according to this law the heat transfers from cup of coffee to the person body until both bodies reaches to the equilibrium state.
After attaining the equilibrium state, the heat transfer may be ceases between the bodies.
Whenever the person touches the hot coffee, he senses the heat that means the heat is transferring in to his body.
By definition, the atomic mass of an element is approximately the sum of the mass of protons and neutrons.
Of the choices given, C makes the most sense.
Answer: C) the number of protons and neutrons in an atom.
From the definition of entropy, the entropy change of an object is
where
Q is the heat absorbed
T is the absolute temperature
in our problem, we have Q=25.0 J, while the absolute temperature is (converting in Kelvin)
and so the entropy change is