Answer:
A. Heat flows from an object at higher temperature to an object at lower temperature
Explanation:
The option A obeys the 2nd law of thermodynamics. The heat will flow from the object at higher temperature to the object at Lower temperature till they reach an equilibrial state.
Heat doesn’t necessarily flow from an object with higher thermal energy to an object with lower thermal energy because an object has a higher thermal energy when it’s mass is more than the other. This makes B wrong.
C is wrong because heat moves from an object with higher temperature to objects with Lower temperature regardless of the state of matter.
Answer:
False.
Explanation:
We usually define vectors in terms of its magnitude and their orientation. Magnitude and direction does not vary with the change of a coordinate system as they are independent of coordinates and will remain the same. So it does not matter what your choice of a coordinate system is, it will not effect its direction and magnitude. However you can resolve the vector in to its components if you want.
The correct option is B.
All objects emit electromagnetic radiation and the amount of radiation emitted at each wavelength depend on the temperature of the object. This observation is described by Wien's law, which states that the black body radiation curve for different temperatures peaks at a wavelength that is inversely proportional to the temperature.
Answer:
v2^2 - v1^2 = 2 g s fundamental formula
v2 = v1 + 2 g = v1 + 19.8 increase in velocity in 2 sec
v1^2 + 39.6 v1 + 392 - v1^2 = 2 * 9.8 * 123.1 = 2412.76
v1 = (2412.76 - 392) / 39.6 = 51.03
v2 = 51.03 + 19.6 = 70.63
T = 70.63 / .8 = 7.207 sec time to fall height of tower
S = 1/2 g T^2 = 4.9 * 7.207^2 = 254.5 m
(Note v2^2 - v1^2 = 70.63^2 - 51.03^2 = 2385 m
2385 / (2 * 9.8) = 122 m (close to 123.1 as was given
