Explanation

Explanation

What is the difference among application, program and software?

Application: A specific software designed to perform a particular task, like word processing or browsing the internet.

Program: A set of instructions written to execute a particular task or solve a problem, which can be part of an application or software.

Software: A broad term that refers to any collection of programs or applications that perform various tasks on a computer system.

Explanation

Differentiate between network and internet.

Network: A network is a group of interconnected computers or devices that can share resources and information, typically within a local area (LAN) or wide area (WAN).

Internet: The internet is a global network of networks that connects millions of private, public, academic, and governmental systems, enabling worldwide communication and information sharing.

Explanation

Ahmad stands at point D, 2m in front of a spotlight at point A. He is 1.6m tall and is facing the wall of a building which is 10.5m away from him. How tall (BC) is his shadow on the wall of the building (5 marks)

To find the height $BC$ of Ahmad's shadow on the wall of the building, we can use the properties of similar triangles.

Given:

1. Ahmad's height $DE = 1.6$ m.
2. Distance from the spotlight at $A$ to Ahmad at $D$is $2$ m.
3. Distance from Ahmad at $D$ to the wall at $B$ is $10.5$ m.
4. Total distance $AB = 2 + 10.5 = 12.5$m.

Using similar triangles:

$$$$BCAB=DEAD​

Substitute the values:

$$frac{BC}{12.5} = frac{1.6}{2}$$ $$BC = 12.5 times frac{1.6}{2} = 12.5 times 0.8 = 10 text{ m}$$

Height $BC = 10$ m.

Explanation

Question: A telephone company charges initially Rs.0.50 and then Rs. 0.11 for every minute. Write an expression that gives the cost of a call that lasts N minutes. (5 marks)

I apple - 2 Rs

8 apples = 2x8

= 16 Rs

Initial charges = Rs 0.5-

Next every min charge = RS0.11 Rs 

No. minutes charges = Nx0.1 =0.11N.R

Total charge = (0.50 +0.11N) Rs

Explanation

Explanation

The perimeter of the rectangle given below is 114 cm. Find the area of the rectangle. (5 marks)

Explanation

(b) How the carbohydrates, proteins, and fats are digested in humans? (5)

Carbohydrates:
Carbohydrates are broken down into glucose by enzymes like amylase in the mouth and small intestine.

Proteins:
Proteins are broken down into amino acids by pepsin in the stomach and proteases in the small intestine.

Fats:
Fats are emulsified by bile and then broken down into fatty acids and glycerol by lipase in the small intestine.

Explanation

Question:

 What are antioxidants and why are they used in foods? Write a short note on natural and synthetic antioxidants. (5 amrks)

Antioxidants:
Antioxidants are compounds that prevent oxidative damage in cells, thus extending the shelf life and quality of foods.

Natural vs. Synthetic:
Natural antioxidants (e.g., vitamin C, E) are derived from plants, while synthetic ones (e.g., BHA, BHT) are lab-made; both help preserve food freshness but vary in sources and stability.

Explanation

NOTE: The question has 4 parts each part of the question contains 5 marks

Question: (a) What is the difference between fog and smog? What are the causes of smog and its effects on human health? Write a short note on one of the latest technologies to eliminate smog and avoid atmospheric pollution. (5)

Difference between Fog and Smog:
Fog is a natural weather phenomenon caused by condensed water vapor, while smog is a type of air pollution formed from pollutants, mainly from vehicles and industry.

Causes of Smog:
Smog is caused by emissions from vehicles, factories,

Effects on Human Health:
Smog can cause respiratory issues, eye irritation

Latest Technology to Eliminate Smog:
Photocatalytic materials, such as titanium dioxide coatings

*

(b)What is the role of oxygen-demanding wastes in water pollution? How it can be prevented? (5)

Role in Water Pollution:
Oxygen-demanding wastes, like organic matter from sewage, agricultural runoff, and industrial discharge, consume oxygen in water as they decompose.

Reducing pollution sources by treating wastewater, promoting sustainable agriculture

*

(c)What is the biosphere? Write a note on the ‘Energy Resources’ available in the biosphere. (5)

The biosphere is the global ecological system that includes all living organisms and their interactions with the Earth's atmosphere, land, and water. Energy resources in the biosphere include solar energy, wind, water, and biomass, which are vital for sustaining life and ecosystems.

*

(d)What are the different layers of the atmosphere? On what basis these layers are classified? In which layer ‘Auroras’ are formed and where do satellites orbit? (5)

The atmosphere consists of five layers: the troposphere, stratosphere, mesosphere, thermosphere, and exosphere, classified based on temperature gradients and altitude.

Auroras form in the thermosphere, while satellites typically orbit in the exosphere.