Students can use Chapter 1 Exploration Entering the World of Secondary Science Question Answer NCERT Solutions as a quick reference guide.

Class 9 Science Exploration Chapter 1 Question Answer

Class 9 Science Ch 1 Exploration Entering the World of Secondary Science Question Answer

Class 9 Science Chapter 1 Exploration Entering the World of Secondary Science Question Answer (InText)

Think It Over (NCERT Textbook Page No. 2)

Question 1.
A cricket shot. Think of a cricket ball being hit for a six. You want to make a simple model. What details would you include? What would you ignore?
Answer:
To model whether a cricket ball will cross the boundary, we focus on key factors like its mass, speed, and direction, while ignoring irrelevant details like bat brand or ball colour. Smaller effects such as air resistance and spin can be neglected in a simple model but added later for greater accuracy.

Think It Over (NCERT Textbook Page No. 4)

Question 2.
How do we check predictions? Varsha told her friend Meghna, “It will rain this afternoon because the clouds look dark”. Think of some questions Meghna could ask Varsha to make this prediction scientifically testable.
Answer:
Good scientific questions focus on measurable evidence and past patterns rather than simple yes/no type of answers. Meghna could ask about humidity, wind, temperature, and previous conditions when it rained to make the prediction testable.

Think It Over (NCERT Textbook Page No. 6)

Question 3.
Estimate how many litres of air you breathe in one day. Start by estimating how many breaths you take per minute, and the volume of one breath. Your aim is not to find an exact answer, but a reasonable estimate.
Answer:
1. Estimating Breaths per day

• Breathing Rate (at rest) 12 – 15 breaths per minute
  Minutes in a day = 60 × 24 = 1440 minutes
• Total breaths:
  Multiplying the rate by the total minutes gives roughly [= (12 – 15) × 1440 = (17280 – 21600)]
  18,000 to 22,000 breaths per day (rounded to approximately 20,000 for the estimation).

2. Estimating volume per breath

It takes about 4 – 5 breaths to fill a standard party balloon.

Balloon volume: Approximately 2 litres

Calculation:
2 litres ÷ 4 breaths = 0.5 litre per breaths.

3. Now, to find the total daily volume, multiply the total no. of breaths by the volume per breath = 2,000 breaths × 0.5 litre/breath = 10,000 litres of air per day.

Pause and Ponder (NCERT Textbook Page No. 4)

Question 1.
Think of a prediction you or your family made recently (for example, the outcome of a cricket match). Was it based on evidence and reasoning, or mainly on guesswork? How can scientific thinking improve such predictions?
Answer:
Recently, my family was trying to predict rain by looking at dark clouds. The prediction was partly based on observation. However, accurate prediction involves scientific data such as humidity, temperature, wind speed, and past weather patterns. It concludes that scientific thinking improves predictions by relying on measurable evidence rather than assumptions.

Pause and Ponder (NCERT Textbook Page No. 6)

Question 2.
Describe one situation where an approximate answer is good enough, and one where you would need a very exact value.
Answer:
An approximate answer is useful when estimating grocery costs for weekly shopping (e.g., ~₹2000 for a family’s needs), allowing quick budgeting without itemising every price.
However, exact values are critical when measuring medicine dosage (e.g., 5 ml paracetamol for a child), as even small errors could lead to overdose or under-treatment.

Question 3.
Choose a real-life object (may be a pressure cooker or a mobile phone) or a problem (maybe a traffic jam near your school). Make a sketch listing what kind of ideas from physics, chemistry, biology, earth science, or mathematics are involved. Show how at least two branches of science connect with your example.
Answer:
A pressure cooker is a perfect mix of science. Physics is the main part – it traps steam to increase pressure, which raises the boiling point of water so food cooks faster. This connects directly to Biology, as the intense heat breaks down tough plant fibers and kills harmful bacteria, making the meal safe and easy to digest. Chemistry also plays a role through the Maillard reaction, which browns the food and creates rich flavours at these high temperatures.