✅ True or False (10 Questions)

1. Pressure is defined as force per unit area.
   True hecu106

2. Broad straps of a bag exert more pressure on shoulders than narrow straps.
   False
   (Broad straps reduce pressure by increasing area.) hecu106

3. The SI unit of pressure is pascal (Pa).
   True hecu106

4. Liquids exert pressure only at the bottom of the container.
   False
   (Liquids exert pressure in all directions, including sides.) hecu106

5. Pressure exerted by a liquid increases with increase in height of the liquid column.
   True hecu106

6. Atmospheric pressure is the pressure exerted by air around us.
   True hecu106

7. Air moves from a region of low pressure to a region of high pressure.
   False
   (Air flows from high pressure to low pressure.) hecu106

8. High-speed winds create a low-pressure area.
   True hecu106

9. Lightning is caused by sudden flow of electric charges in clouds.
   True hecu106

10. The eye of a cyclone is the region with the strongest winds and heavy storms.
    False
    (The eye is calm; strong winds occur around it.)

✅ Fill in the Blanks (10 Questions)

1. Pressure is defined as force divided by __________.
   Answer: area hecu106

2. The SI unit of pressure is __________.
   Answer: pascal (Pa) hecu106

3. Liquids exert pressure in all __________.
   Answer: directions hecu106

4. Pressure exerted by a liquid increases with increase in the __________ of the liquid column.
   Answer: height hecu106

5. The pressure exerted by air around us is called __________ pressure.
   Answer: atmospheric hecu106

6. Air moves from a region of __________ pressure to a region of low pressure.
   Answer: high hecu106

7. Winds are formed due to differences in __________.
   Answer: pressure hecu106

8. High-speed winds reduce the air __________.
   Answer: pressure hecu106

9. A device used to protect buildings from lightning is called a lightning __________.
   Answer: conductor hecu106

10. The calm central region of a cyclone is called the __________ of the cyclone.
    Answer: eye

✅ Multiple Choice Questions (15 MCQs)

1. Pressure is given by the formula:

A. Force × Area
B. Force ÷ Area
C. Area ÷ Force
D. Force + Area
✅ Answer: B hecu106

2. The SI unit of pressure is:

A. Newton
B. Joule
C. Pascal
D. Watt
✅ Answer: C hecu106

3. Broad straps reduce pressure because they:

A. Increase force
B. Increase area
C. Decrease weight
D. Increase speed
✅ Answer: B hecu106

4. Liquids exert pressure:

A. Only upward
B. Only downward
C. Only sideways
D. In all directions
✅ Answer: D hecu106

5. Pressure exerted by water depends on:

A. Colour of water
B. Height of water column
C. Shape of container
D. Temperature only
✅ Answer: B hecu106

6. Atmospheric pressure is exerted by:

A. Water
B. Soil
C. Air
D. Fire
✅ Answer: C hecu106

7. Winds blow because of difference in:

A. Temperature only
B. Pressure
C. Humidity only
D. Gravity
✅ Answer: B hecu106

8. Air moves from:

A. Low pressure to high pressure
B. High pressure to low pressure
C. Hot region to cold region only
D. Sea to land always
✅ Answer: B hecu106

9. High-speed winds create:

A. High pressure area
B. Low pressure area
C. No pressure
D. Constant pressure
✅ Answer: B hecu106

10. Lightning occurs due to:

A. Magnetic attraction
B. Electric discharge in clouds
C. Pressure in oceans
D. Wind blowing
✅ Answer: B hecu106

11. A lightning conductor is used to:

A. Increase rainfall
B. Protect buildings from lightning
C. Create storms
D. Stop winds
✅ Answer: B hecu106

12. Cyclones are caused due to:

A. Strong winds and low pressure
B. Snowfall
C. Earthquakes
D. Volcanoes
✅ Answer: A hecu106

13. The calm central region of a cyclone is called:

A. Storm zone
B. Eye
C. Tail
D. Cloud region
✅ Answer: B hecu106

14. The strongest winds in a cyclone occur:

A. Inside the eye
B. Around the eye
C. At the centre only
D. Under the sea
✅ Answer: B hecu106

15. During a thunderstorm, the safest place is:

A. Under a tree
B. Open field
C. Inside a building
D. On a rooftop
✅ Answer: C

✅ Assertion–Reason Questions (10)

Directions: Choose the correct option:

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not the correct explanation of A
C. A is true but R is false
D. A is false but R is true

1.

Assertion (A): Pressure is force acting per unit area.
Reason (R): Pressure increases when the same force acts on a smaller area.
✅ Answer: A hecu106

2.

Assertion (A): Broad straps of a bag reduce pressure on shoulders.
Reason (R): Broad straps increase the area over which force acts.
✅ Answer: A hecu106

3.

Assertion (A): Liquids exert pressure in all directions.
Reason (R): Liquid particles can move freely in all directions.
✅ Answer: A hecu106

4.

Assertion (A): Pressure exerted by water increases with depth.
Reason (R): The height of the water column above increases pressure.
✅ Answer: A hecu106

5.

Assertion (A): Atmospheric pressure acts on all objects around us.
Reason (R): Air has weight and exerts pressure.
✅ Answer: A hecu106

6.

Assertion (A): Winds are formed due to pressure differences.
Reason (R): Air moves from high pressure region to low pressure region.
✅ Answer: A hecu106

7.

Assertion (A): High-speed winds can lift roofs of houses.
Reason (R): Fast-moving air creates low pressure above the roof.
✅ Answer: A hecu106

8.

Assertion (A): Lightning is an electric discharge.
Reason (R): Electric charges build up in clouds during storms.
✅ Answer: A hecu106

9.

Assertion (A): The eye of a cyclone is calm.
Reason (R): Strong winds rotate around the eye, leaving the centre peaceful.
✅ Answer: A hecu106

10.

Assertion (A): A lightning conductor protects buildings.
Reason (R): It provides a safe path for electric charge to reach the ground.
✅ Answer: A

✅ Very Short Answer Questions (10 Questions)

(2 Marks Each | CBSE Class 8 Standard | Good Quality)

1. Define pressure.

Answer:
Pressure is the force acting per unit area of a surface.
Pressure = Force ÷ Area. hecu106

2. Why do broad straps reduce pressure on shoulders?

Answer:
Broad straps increase the area over which the force acts, thus reducing pressure on the shoulders. hecu106

3. What is the SI unit of pressure?

Answer:
The SI unit of pressure is pascal (Pa). hecu106

4. Do liquids exert pressure only at the bottom?

Answer:
No, liquids exert pressure in all directions—at the bottom and on the sides of the container. hecu106

5. What is atmospheric pressure?

Answer:
Atmospheric pressure is the pressure exerted by the weight of air around us on all objects. hecu106

6. Why does air move from high pressure to low pressure?

Answer:
Air moves from high pressure to low pressure to balance the pressure difference, creating winds. hecu106

7. What causes strong winds during storms?

Answer:
Strong winds are caused due to large pressure differences created by uneven heating of air. hecu106

8. What is lightning?

Answer:
Lightning is a sudden electric discharge between clouds or between clouds and Earth during a storm.

9. What is the eye of a cyclone?

Answer:
The eye of a cyclone is the calm central region of the cyclone surrounded by strong rotating winds. hecu106

10. What is the function of a lightning conductor?

Answer:
A lightning conductor protects buildings by providing a safe path for electric charges to pass into the ground.

✅ Short Answer Questions (10 Questions)

(3 Marks Each | CBSE Class 8 Standard | Good Quality)

1. Explain why pressure increases when area decreases.

Answer:
Pressure is force per unit area. When the same force acts on a smaller area, the pressure becomes greater. This is why sharp objects like needles exert more pressure than blunt objects. hecu106

2. How do liquids exert pressure?

Answer:
Liquids exert pressure in all directions. They press not only at the bottom of the container but also on its sides. Liquid pressure increases with depth or height of the liquid column. hecu106

3. Why is pressure at the bottom of a tank more than at the top?

Answer:
Pressure in liquids increases with depth because the weight of the liquid column above exerts more force. Therefore, the bottom of a tank experiences greater pressure. hecu106

4. What is atmospheric pressure? How can it be shown by an activity?

Answer:
Atmospheric pressure is the pressure exerted by air around us. It can be shown by pressing a rubber sucker on a smooth surface. It sticks due to atmospheric pressure pushing it against the surface. hecu106

5. How are winds formed?

Answer:
Winds are formed due to differences in air pressure. Air moves from a high-pressure region to a low-pressure region. Uneven heating of Earth’s surface creates these pressure differences. hecu106

6. Why can high-speed winds blow off roofs?

Answer:
Fast-moving air creates low pressure above the roof. The higher pressure inside the house pushes the roof upward, sometimes blowing it off during storms. hecu106

7. What is lightning? How is it produced?

Answer:
Lightning is an electric discharge during storms. Charges build up in clouds due to friction between water droplets and ice particles. When the charge difference becomes large, electricity flows suddenly, producing lightning. hecu106

8. What safety measures should be taken during a thunderstorm?

Answer:
During a thunderstorm, one should stay indoors, avoid standing under trees, not use electrical appliances, and stay away from open fields or metal objects. hecu106

9. What is a cyclone?

Answer:
A cyclone is a violent rotating storm formed over warm oceans due to low pressure and strong winds. It brings heavy rain, high-speed winds, and destruction. hecu106

10. Explain the structure of a cyclone.

Answer:
A cyclone has a calm centre called the eye. Around the eye, strong rotating winds and dense clouds cause heavy rain and stormy conditions. The strongest winds occur near the eye wall.

✅ Case-Based Questions (4 Cases)

(4 Marks Each | Sub-questions: 1 + 1 + 2 Marks)
CBSE Competency-Based Standard

Case 1: Broad and Narrow Straps

A student carries a heavy school bag. He notices that bags with broad straps feel more comfortable than bags with narrow straps.

Questions:

Q1. (1 Mark) What physical quantity is involved here?
Answer: Pressure hecu106

Q2. (1 Mark) Which strap exerts less pressure?
Answer: Broad strap hecu106

Q3. (2 Marks) Why do broad straps reduce pain on shoulders?
Answer:
Broad straps increase the area over which the force acts, so pressure decreases and the bag feels more comfortable. hecu106

Case 2: Pressure in Liquids

An overhead water tank supplies water to houses. Water flows with more force on the ground floor compared to upper floors.

Questions:

Q1. (1 Mark) What does this show about liquid pressure?
Answer: Liquid pressure increases with depth. hecu106

Q2. (1 Mark) Where is water pressure maximum?
Answer: At the bottom of the tank. hecu106

Q3. (2 Marks) Why does water flow with more force at lower levels?
Answer:
Because the height of water column above is greater, exerting more pressure at lower levels. hecu106

Case 3: Formation of Winds

During the day, land heats up faster than the sea. Warm air above land rises, and cooler air from the sea moves towards land.

Questions:

Q1. (1 Mark) What is this movement of air called?
Answer: Wind hecu106

Q2. (1 Mark) Air moves from high pressure to ________ pressure.
Answer: Low hecu106

Q3. (2 Marks) Why does wind blow from sea to land during daytime?
Answer:
Land becomes hotter and creates low pressure, so cooler high-pressure air from the sea moves towards land. hecu106

Case 4: Cyclone and Safety

A cyclone forms over warm ocean waters and moves towards the coast, bringing strong winds and heavy rain.

Questions:

Q1. (1 Mark) What is the calm centre of a cyclone called?
Answer: Eye hecu106

Q2. (1 Mark) Where are the strongest winds found in a cyclone?
Answer: Around the eye hecu106

Q3. (2 Marks) Mention two safety measures during a cyclone.
Answer:
Stay indoors or in a safe shelter, avoid open areas, follow weather warnings, and keep emergency supplies ready.

✅ Long Answer Questions (5 Questions)

(5 Marks Each | CBSE Class 8 Standard | High Quality Answers)

1. Define pressure and explain how area affects pressure with examples.

Answer:
Pressure is defined as the force acting per unit area.Pressure=ForceAreaPressure = \frac{Force}{Area}Pressure=AreaForce​

If the same force acts on a smaller area, pressure increases.
Example: A sharp knife cuts easily because the force acts on a small area.
Broad straps of bags reduce pressure because the force is distributed over a larger area.

Thus, pressure depends on both force and area. hecu106

2. Explain how liquids exert pressure and why pressure increases with depth.

Answer:
Liquids exert pressure in all directions—at the bottom and on the sides of the container.

Pressure exerted by a liquid depends on the height of the liquid column above a point.
Greater depth means more liquid above, so more weight acts downward, increasing pressure.

Example: Water pressure is higher at the bottom of a tank, which is why dams are built thicker at the base. hecu106

3. What is atmospheric pressure? Describe an activity that proves its existence.

Answer:
Atmospheric pressure is the pressure exerted by the weight of air surrounding Earth.

Activity:

A rubber sucker is pressed against a smooth surface. It sticks firmly.

This happens because air inside the sucker is pushed out, creating low pressure inside. The atmospheric pressure outside pushes the sucker against the surface.

Thus, this proves that atmospheric pressure acts on objects around us. hecu106

4. Explain the formation of winds and thunderstorms.

Answer:
Winds are formed due to differences in air pressure.

• When air is heated, it becomes lighter and rises, creating low pressure.
• Cooler air from high-pressure areas moves towards low-pressure areas, forming wind.

Thunderstorms occur when warm moist air rises rapidly, forming clouds. Electric charges build up in clouds, leading to lightning and thunder.

Thus, pressure difference and heating play major roles in wind and storms. hecu106

5. What is a cyclone? Describe its structure and safety measures.

Answer:
A cyclone is a violent rotating storm formed over warm ocean waters due to low pressure.

Structure:

• The centre is calm and called the eye.
• Strong rotating winds occur around the eye wall.
• Cyclones bring heavy rain and destruction.

Safety Measures:

• Stay indoors or in cyclone shelters.
• Avoid open fields and coastal areas.
• Follow weather warnings.
• Keep emergency supplies ready.

Thus, cyclones are dangerous natural disasters requiring proper preparedness.