Why can we never create energy?
A) because it is impossible to create the fundamental particles such as electrons and protons
B) because energy is always conserved
C) because of the equivalence of mass and energy
D) because matter is always conserved
E) Actually, we do create energy frequently in the lab.
B
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Projectile Motion: Shown below are the velocity and acceleration vectors for an object in several different types of motion. In which case is the object slowing down and turning to its right?
A. 
B. 
C. 
D. 
E. 
An electromagnetic wave is propagating towards the west in free space. At a certain moment the direction of the magnetic field vector associated with this wave points vertically upward. What is the direction of the electric field vector?
A) horizontal and pointing south B) vertical and pointing down C) horizontal and pointing north D) vertical and pointing upward E) horizontal and pointing east
Each of the following lists two facts. Which pair of facts can be used with Newton's version of Kepler's third law to determine the mass of the Sun?
A) Earth is 150 million km from the Sun and orbits the Sun in one year. B) Mercury is 0.387 AU from the Sun and Earth is 1 AU from the Sun. C) The mass of Earth is 6 × 1024 kg and Earth orbits the Sun in one year. D) Earth rotates in one day and orbits the Sun in one year.
As a projectile moves along its parabolic trajectory, which of the following remain constant (ignoring air resistance, and defining the z axis as pointing upward)?
A. Its speed B. Its velocity C. Its x-velocity and y-velocity D. Its z-velocity E. Its acceleration F. Its x-velocity, y-velocity, and acceleration T. Some other combination of the given quantities