Physics in Daily Life and Nation

Try these questions

5 questions from this lesson’s quiz. Start the lesson to answer them and see the right answers.

1. 1. Small gaps are left between steel rail segments on the Standard Gauge Railway (SGR). What is the main reason for these gaps?

   • A. To make the train run more quietly
   • B. To reduce friction between the wheels and the rails
   • C. To allow the steel to expand on hot days without buckling
   • D. To let rainwater drain away from the track

2. 2. The handle of an aluminium sufuria is usually made of wood or bakelite. Why?

   • A. Wood and bakelite are better conductors of heat than aluminium
   • B. Wood and bakelite expand more than aluminium when heated
   • C. Wood and bakelite are heavier than aluminium
   • D. Wood and bakelite are poor conductors of heat, so the handle stays cool to hold

3. 3. An electric motor is supplied with 2500 J of electrical energy and produces 1750 J of useful kinetic energy. Calculate its efficiency as a percentage.

   Type your answer (in %) in the lesson.

4. 4. Hydraulic brakes in a matatu transmit the pressure from the brake pedal through the brake fluid to the brake discs. Name the principle that explains this.

   Type your answer in the lesson.

5. 5. Electricity is sent through a power line at double the original voltage, with the same power delivered. The current is halved. Power loss in the cables is given by P = I^2 R. How does the power loss in the same cable change?

   • A. It is halved
   • B. It becomes one quarter of the original
   • C. It is doubled
   • D. It becomes four times the original

More in Introduction to Physics

• ▸Nature and Meaning of Physics
• ▸Core Branches of Physics
• ▸Modern Branches of Physics
• ▸Relationship of Physics to Other Disciplines
• ▸Physics Career Pathways
• ▸Introduction to Pressure and Solid Pressure
• ▸Atmospheric Pressure and Its Demonstrations
• ▸Pressure in Liquids and Depth

See every Grade 10 Physics lesson →