#### Question 1

If a ship moves from freshwater into seawater, it will

(a) Sink completely
(b) Sink a little bit
(c) Rise a little higher
(d) Remain unaffected

#### Question 2

Which of the following statement(s) about the asteroid belt (小行星帶) is/are correct?

(a) I and II
(b) II only
(c) III only
(d) I and III

#### Question 3

Which statement(s) is/are correct about Venus?

(a) II and III
(b) I only
(c) I, II and III
(d) I, III and IV

#### Question 4

Arrange the following distances in increasing order:

(a) I, II, III, IV, V
(b) II, I, III, IV, V
(c) II, I, III, V, IV
(d) V, IV, I, III, II

#### Question 5

Proxima Centauri (毗鄰星) is about 4.2 light-years from us. Which statement is wrong?

(a) The distance between the Sun and us is shorter than 4.2 light-years.
(b) It takes approximately 4.2 years for light to travel from Proxima Centauri to the Earth.
(c) Proxima Centauri is inside Milky Way Galaxy (銀河系).
(d) Proxima Centauri is inside the solar system (太陽系).

#### Question 6

Did you know that the name of the inventor who was credited with inventing the computer chip smart card now widely used by banks, supermarkets, mobile phone SIM cards, identity documents, and driving licenses?

(a) Roland Moreno
(b) Nikola Tesla
(c) Louis Braille
(d) Charles Babbage

#### Answer

Question 1: (c) Rise a little higher

When a body is immersed in a fluid, the fluid exerts an upward force on it, which is called buoyant force. According to Archimedes’ principle,
Buoyant force = Vi x PI x G
where
Vi = Volume of immersed part of body
PI = density of fluid
G = acceleration due to gravity
As the density of seawater is higher than that of the freshwater, it exerts more buoyant force on ship and as a result, ship will rise a little higher.

Question 2: (c) III only

Statement I is not correct because there is a dwarf planet called “Ceres” located in the asteroid belt. It is very large.
Statement II is not correct because most of the short-period comets come from another belt beyond Neptune.
Only Statement III is correct.

Question 3: (c) I, II and III

Venus’s atmosphere contains a lot of carbon dioxide and hence it has a severe Greenhouse effect which causes it to be very hot (Venus’s surface temperature is about 465°C). Also, Venus’s rotation is from East to West which is different from Earth. However, Venus does not have any satellites.

Question 4: (b) II, I, III, IV, V

The Moon is a satellite of the Earth so that it is the smallest. The Sun is a star which is much larger than a planet like the Earth. Our solar system is just one of the systems in the Milky Way Galaxy.

Question 5: (d) Proxima Centauri is inside the solar system (太陽系).

(a) is correct because the Sun is the closest star. (b) is correct since one light-year is equivalent to the distance for the light to travel by one year. (c) is correct because Proxima Centauri is a member of the Milky Way Galaxy. (d) is wrong because the size of our solar system is smaller than 4.2 light-years. Therefore, Proxima Centauri must be outside the solar system.

Question 6: (a) Roland Moreno

Roland Moreno was a French inventor who invented the computer chip smart card and its first patent file dated back to 1974. It was a major invention, and the inventor famously said that he got the idea in a dream.
Nikola Tesla was a Serbian-American inventor who was best known for his contributions to the design of the modern alternating current supply system.
Louis Braille was a French educator and inventor of a system of reading and writing for use by the blind or visually impaired.
Charles Babbage was an English inventor who originated the concept of the digital programmable computer.