Force Friction Pressure and Sound (Class 8)

What this worksheet covers

This is an eighteen-question practice worksheet on force, friction, pressure and sound for Class 8, written to the pattern of the SOF National Science Olympiad (NSO). It carries 24 marks and is designed to be attempted in 45 minutes, split across three sections — Scientific Reasoning, Applying What You Know and Achievers Section. Every question is multiple choice with exactly one correct option, and every one comes with a fully worked solution rather than just an answer key — so a child who gets one wrong can see where the reasoning went astray instead of only learning that it did.

Skills your child practises

• Applied problem-solving on force, friction, pressure and sound at Class 8 level
• Working accurately against a time limit, as the real paper demands
• Scientific Reasoning questions in the olympiad format
• Applying What You Know questions in the olympiad format
• Achievers Section questions in the olympiad format
• Reading worked solutions to find the step that went wrong

How to use it

1. 1There are 18 questions in this worksheet. All questions are compulsory.
2. 2Each question has four options (A), (B), (C) and (D). Exactly one option is correct.
3. 3Questions 1–15 carry 1 mark each. Questions 16–18 (Achievers Section) carry 3 marks each.
4. 4There is no negative marking. Study every diagram and table carefully.

Sample questions from this worksheet

A preview of what's inside Force Friction Pressure and Sound (Class 8) — the PDF has the full set, and every question comes with a worked solution like these.

1. 1. The SI unit of force is the _______.

   • ANewtoncorrect
   • BJoule
   • CPascal
   • DWatt
   Solution: Force is measured in newtons (N). The joule is the unit of energy, the pascal of pressure and the watt of power.

2. 2. A force of 200 N acts on an area of 0.5 m². What is the pressure?

   • A100 Pa
   • B200 Pa
   • C400 Pacorrect
   • D1,000 Pa
   Solution: Pressure = force ÷ area
   = 200 ÷ 0.5 = 400 Pa.

3. 3. Consider the following statements.(i) Friction is always undesirable and should be removed completely.(ii) Liquids exert pressure on the walls of their container as well as on the base.(iii) Sound travels faster in solids than in air.Which of the statements is/are correct?

   • A(i) and (ii) only
   • B(ii) and (iii) onlycorrect
   • C(i) and (iii) only
   • DAll three
   Solution: Statement (i) is false — without friction we could not walk, write, hold objects or apply brakes, so it is useful as well as wasteful. Statement (ii) is true; this is why a hole low in a tank squirts water sideways. Statement (iii) is true, because the particles of a solid are packed closely and pass the vibration on quickly. Hence (ii) and (iii).