To increase the number of snowmen destroyed, you would want more energy and all of the above would increase the energy of the system so D.
The last one. Opposites attract while similar ones repulse each other so all forces are pushing them apart
Answer:
Alpha = ω^2 R where R is radius of blade
g = w^2 r where r is distance from center
ω^2 R = 11.5 ω^2 r
R / r = 11.5 / 9.8 = 1.17
Or r = .852 R
Since the angular acceleration depends on both R and ω it seems that one can only get r as it depends on R
Rock is completely immersed in hot water. By the second law of thermodynamics, thermal energy or heat is transferred from substance with higher temperature to substance with lower temperature until they come to thermal equilibrium i.e. both at same temperature.
It is given here that rock is at 20°C which is at lower temperature than water at 80°C. ∴Heat or thermal energy flows from water to rock. So, right choice is-
A. The water gives the rock thermal energy and gets no thermal energy in return.
