Solving Sentence Rearrangement: Energy Sources History

This question asks us to arrange four jumbled sentences (P, Q, R, S) into a coherent paragraph between a fixed opening sentence (S1) and a fixed closing sentence (S6).

Let's first read the fixed sentences S1 and S6:

• S1: Civilization dawned when early man learnt how to produce heat and energy by burning wood.
• S6: When they have been used, they cannot be replaced.

S1 talks about the earliest form of energy use (burning wood). S6 talks about something that cannot be replaced once used, strongly suggesting non-renewable resources, which likely follows a discussion of such resources.

Now let's look at the jumbled sentences:

• P: Then steam was used to produce electricity.
• Q: In this century great use has been made of oil and natural gas and the use of atomic reactors has also provided another source of energy.
• R: Much later, the first industrial revolution was based on the production of steam by burning coal.
• S: But none of these fuels is renewable.

We need to find a logical flow connecting S1 to S6 through P, Q, R, and S.

Step-by-Step Analysis for Sentence Sequencing

Let's analyze the connections between the sentences:

1. S1 introduces the burning of wood. Sentence R says "Much later", introducing coal and steam production for the first industrial revolution. This is a logical progression from S1, discussing the next major energy source in history. So, R should likely follow S1.
2. Sentence P talks about using "Then steam was used to produce electricity". The word "Then" suggests this follows the introduction or production of steam. Sentence R talks about producing steam by burning coal. Therefore, P seems to follow R, explaining a subsequent use of the steam introduced in R.
3. Sentence Q talks about energy sources used "In this century", mentioning oil, natural gas, and atomic reactors. This represents a more modern development compared to wood, coal, and early steam use. It should come later in the sequence, likely after R and P, which describe earlier periods.
4. Sentence S states, "But none of these fuels is renewable." The phrase "these fuels" refers to the energy sources mentioned previously. Looking at R (coal) and Q (oil, natural gas, atomic), these are indeed non-renewable sources. S serves as a conclusion or comment on the nature of the fuels discussed before it. Since S6 elaborates on the non-renewability ("cannot be replaced"), S should immediately precede S6, summarizing that the discussed fuels (from R and Q) are non-renewable.

Constructing the Sequence

Based on the analysis:

• R follows S1 (history of energy sources).
• P follows R (use of steam produced in R).
• Q follows P (newer energy sources).
• S follows Q (comment on the non-renewability of fuels from R and Q).
• S6 follows S (elaboration on non-renewability).

This gives us the sequence R → P → Q → S.

Let's check this sequence in context:

S1: Civilization dawned when early man learnt how to produce heat and energy by burning wood.

R: Much later, the first industrial revolution was based on the production of steam by burning coal.

P: Then steam was used to produce electricity.

Q: In this century great use has been made of oil and natural gas and the use of atomic reactors has also provided another source of energy.

S: But none of these fuels is renewable.

S6: When they have been used, they cannot be replaced.

This arrangement makes logical sense and flows smoothly, discussing the evolution of energy sources from wood to coal/steam, then steam for electricity, to modern sources like oil, gas, and atomic energy, and finally commenting on their non-renewable nature.

Final Sequence

The proper sequence of the four sentences is R P Q S.

Revision Table: Paragraph Jumbling Strategy

Solving paragraph jumbling questions requires identifying connections between sentences. Here are key strategies:

• Read S1 and S6 carefully to understand the topic and the overall direction.
• Look for transition words (e.g., "Then", "Much later", "But", "Therefore") that indicate relationships between sentences.
• Identify pronouns (e.g., "these fuels", "they") and determine what nouns they refer to in previous sentences.
• Follow the flow of ideas, whether it's chronological, cause and effect, general to specific, etc.
• Try linking pairs of sentences first (e.g., R and P seem connected).
• Once a potential sequence is formed, read the entire paragraph (S1 + sequence + S6) to check for logical coherence and smooth transitions.

Additional Information: Types of Energy Resources

The passage discusses various energy sources. Energy resources are broadly classified into two categories:

• Renewable Resources: These are natural resources that are replenished at a rate equal to or faster than the rate at which they are consumed. Examples include solar energy, wind energy, hydro energy, geothermal energy, and biomass.
• Non-renewable Resources: These are resources that exist in a fixed amount or are consumed much faster than they are replenished by natural processes. Once depleted, they are essentially gone on a human timescale. Examples include fossil fuels (coal, petroleum, natural gas) and nuclear fuels (like uranium, although the fission process can be managed for longer terms than fossil fuels).

The passage highlights the historical shift from wood (renewable, but usage rate can exceed replenish rate if not managed) to major non-renewable sources like coal, oil, and natural gas, and also mentions atomic energy, which uses nuclear fuels (non-renewable in the context of readily available fissile materials). S and S6 specifically point out the key characteristic of the resources discussed in R and Q – their non-renewable nature.