As an object moves from point A to point B only two forces act on it: one force is conservative and does -70 J of work, the other force is nonconservative and does +50 J of work. Between A and B,
a. the kinetic energy of object increases, mechanical energy increases.
b. the kinetic energy of object decreases, mechanical energy increases.
c. the kinetic energy of object decreases, mechanical energy decreases.
d. the kinetic energy of object increases, mechanical energy decreases.
e. None of the above.
B
You might also like to view...
The air in a closed room has
1) mass, 2) energy, 3) weight, 4) all of these, 5) none of these, and the greater the rate of molecular motion in the air, the greater the 6) temperature. 7) molecular kinetic energy. 8) air pressure. 9) all of these. 10) none of these.
Why must the Sun's rate of fusion gradually rise over billions of years?
A) The Sun becomes less efficient and must increase the rate of fusion to produce the same amount of energy. B) Fusion reactions decrease the overall number of particles in the core, causing the core to shrink, converting gravitational potential energy into thermal energy, and increasing the rate of fusion. C) The radiation produced by fusion reactions that is trapped in the core gradually raises the temperature, increasing the rate of fusion. D) The Sun gets heavier as it gets older, and the stronger inward pull of gravity increases the fusion rate. E) The rate of fusion is not rising; it is actually decreasing over time.
The banking angle in a turn on the Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lower coming out of the turn
Why do they do this? A) to reduce the g-force on them B) to increase the g-force on them C) to prevent the bobsled from turning over D) to take the turn at a faster speed E) to give the team better control, because they are able to see ahead of the turn
The__________is a graph that separates the effects of temperature and surface area on stellar luminosities and enables astronomers to sort the stars according to their diameters
A) Herzberg diagram B) Hertzsprung-Russell diagram C) Ptolemaic geocentric D) Maxam-model