Physical Quantities and Measurement
- Unit and Its Types
- Unit Systems
- Physical Quantities
- Rules and Conventions for Writing SI Units and Their Symbols
- International System of Units (SI System)
- Unit Prefixes
- Measurement of Length
- Devices for Measuring Length
- Measurement of Mass
- Devices for Measuring Mass
- Measurement of Time
- Devices for Measuring Time
- Measuring Temperature
- Area and It’s Unit
- Measurement of Area
Select the correct statement :
(a) A wheel barrow is a lever of class I.
(b) The efficiency of a machine is always 100%
(c) Friction in moving parts of a machine reduces its efficiency.
(d) No lever has the mechanical advantage greater than 1.
(e) It is easier to lift a load vertically up than to push it along an inclined plane.
(f) A screw is made by two inclined planes placed together.