A dog is standing in the bed of a pickup truck. The bed is coated with ice, causing the force of friction between the dog and the truck to be zero
The truck is initially at rest, and then accelerates to the right, moving along a flat road. As seen from a stationary observer (watching the truck move to the right), the dog
A) does not move left or right, but the back of the truck moves towards the dog.
B) moves to the right, but not as quickly as the truck is moving to the right, causing it to slide towards the back of the truck.
C) moves to the right at the same rate as the truck, so it doesn't slide.
D) moves to the left, as the truck moves to the right, causing the dog to slide towards the back of the truck.
Answer: A
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A U-tube is partially filled with water and then an immiscible liquid is added to the right side. The top of the liquid is a distance h1 above the level of interface between the liquid and water. On the left side of the tube the top of the water is a distance h2 above the liquid-water interface on the right side. What is the density of the liquid in terms
of the density of water 
.
a.
How is it possible that today's diverse universe was able to arise from that which was very homogeneous at its first moments?
A) Inflation magnified ultrasmall quantum variations in position and momenta. B) There is evidence of a second, slightly smaller Big Bang that took place very shortly after the initial Big Bang, which would account for the variation in structure. C) The rapidly cooling universe created massive quantities of hydrogen, and then helium, which interacted with each other to create regions of relative structure. D) Entropy immediately came into effect, slowing down some areas of expansion, while increasing others.
The flat rotation curves of spiral galaxies tell us that they contain a lot of dark matter. Do they tell us anything about where the dark matter is located within the galaxy?
A) Yes, they tell us that dark matter is spread throughout the galaxy, with most located at large distances from the galactic center. B) Yes, they tell us that dark matter is concentrated near the center of the galaxy. C) Yes, they tell us that dark matter is spread uniformly throughout the galactic disk. D) No, we cannot determine anything about the location of dark matter from the rotation curve.
If you took a Ferris wheel ride in space while sitting on a bathroom scale, your weight
A. would increase and decrease just as on Earth. B. would be constant and larger than zero for the entire ride. C. would start large and continually decrease. D. would start small and continually increase. E. would be zero for the entire ride.