Chapter-6 Pressure — Online MCQ Test
SCIENCE · Grade 8 · CBSE(NCERT)
Practice Chapter-6 Pressure with a free chapter-wise online MCQ test.
This chapter covers: Winds.
AI-generated questions from basic to board-exam level, with instant results and explanations.
Chapter-6 Pressure — Important Questions & Answers
What is pressure defined as in physics?
- A. Force applied per unit area
- B. Total force acting on an object
- C. Weight of an object
- D. Density of a substance
Answer: A. Force applied per unit area
Pressure is the force exerted per unit area. It is calculated as Pressure = Force/Area.
Pressure is the force exerted per unit area. It is calculated as Pressure = Force/Area.
Which of the following is the SI unit of pressure?
- A. Newton
- B. Pascal
- C. Joule
- D. Watt
Answer: B. Pascal
Pascal (Pa) is the SI unit of pressure. It is equivalent to 1 Newton per square meter (N/m²).
Pascal (Pa) is the SI unit of pressure. It is equivalent to 1 Newton per square meter (N/m²).
A nail has a pointed tip because:
- A. Pointed tips look better
- B. The pointed tip has smaller area, producing greater pressure on the surface
- C. Pointed tips are cheaper to manufacture
- D. It helps carry more weight
Answer: B. The pointed tip has smaller area, producing greater pressure on the surface
A nail's pointed tip has a very small area. Since pressure = force/area, the same force produces much higher pressure, allowing it to penetrate surfaces easily.
A nail's pointed tip has a very small area. Since pressure = force/area, the same force produces much higher pressure, allowing it to penetrate surfaces easily.
Compare two scenarios: (1) A 50 N force on 5 m² area, (2) A 100 N force on 10 m² area. Which has greater pressure?
- A. Scenario 1 has greater pressure
- B. Scenario 2 has greater pressure
- C. Both have equal pressure
- D. Cannot be determined
Answer: C. Both have equal pressure
Scenario 1: P = 50/5 = 10 Pa. Scenario 2: P = 100/10 = 10 Pa. Both produce equal pressure despite different forces and areas.
Scenario 1: P = 50/5 = 10 Pa. Scenario 2: P = 100/10 = 10 Pa. Both produce equal pressure despite different forces and areas.
In a hurricane, why is the center (eye) characterized by calm winds and low pressure?
- A. Wind doesn't exist at the center
- B. The extremely low pressure creates a region where air converges but rotates around it rather than moving inward
- C. High pressure blocks wind from entering
- D. The eye is shielded by clouds
Answer: B. The extremely low pressure creates a region where air converges but rotates around it rather than moving inward
The hurricane's eye has the lowest pressure in the system. Air tries to rush inward but is deflected by the Coriolis effect, creating a calm, rotating center.
The hurricane's eye has the lowest pressure in the system. Air tries to rush inward but is deflected by the Coriolis effect, creating a calm, rotating center.