Question

See the attachment and answer the questions​

Answer 1

• 1. Characteristics of standard units.

standard units should be easily understable.

standard units should not change with place or time.

standard units should be in accordance with the size of the quality to be measured.

standard units should be changed with change in physical factors.

• 2. The base units for length, mass and time in these systems were as follows : In CGS system they were centimetre, gram and second respectively.

• 3. Submultiples of kilogram are decagram ,centigram etc. And multiples of kilogram is megagram(1 tonne) , gigagram etc.

• 4. A beam balance works on the principle of moments(stated and proved above) according to which in equilibrium, the anticlockwise moment due to the weight of an object on the left pan of the beam is equal to the clockwise moment due to the standard weights of the right pan of the beam.

• 5. Temperature is a physical quantity that expresses hot and cold. It is the manifestation of thermal energy, present in all matter, which is the source of the occurrence of heat, a flow of energy, when a body is in contact with another that is colder or hotter.

• 6. Lower fixed point of celsius scale is 0°C.Upper fixed point of celsius scale is 100°C. The celsius scale has 100 equal intervals.

• 7. The Celsius scale of the metric system is named after Swedish astronomer Anders Celsius (1701–1744). The Celsius scale sets the freezing point and boiling point of water at 0°C and 100°C respectively. The distance between those two points is divided into 100 equal intervals, each of which is one degree.

• 8. The Fahrenheit scale is now usually defined by two fixed points: the temperature at which pure water ice melts is defined as 32 °F and the boiling point of water is defined to be 212 °F, both at sea level and under standard atmospheric pressure (a 180 °F separation).

• 9. A laboratory thermometer, which is colloquially known as the lab thermometer, is used for measuring temperatures other than the human body temperature. It ranges from -10˚C to 110˚C. Laboratory thermometers are designed for lab purposes such as checking boiling point, freezing point, or temperature of other substances.

• 10. A meter rod is made of iron or wood is used by cloth merchants for measuring cloth. It looks like a long scale, it has different designs. It is made of iron or wood.

• 11. The sundial works on the principle that when the sun is at highest point in the sky the image of an object formed by its light is smallest and when it is at the lowest point the image formed is the longest. The most major drawback of sundial is that it cannot be used in the night.

• 12. Physical balance is used in laboratories to measure mass accurately for the smaller objects.

• 13. The examples of day-to-day approximations are:

1. We add sugar or salt while cooking by estimating its quantity.
2. For reaching your destination we estimate the time required to cover the distance before leaving home.

• 14. Measuring Temperature on Two Scales
• Measuring Temperature on Two ScalesFahrenheit and Celsius are two different scales for measuring temperature. A thermometer measuring a temperature of 22° Celsius is shown here. On the Celsius scale, water freezes at 0° and boils at 100°.

Answer 2

Answer:

(1) It should be of convenient size.

• It should not change with respect to place and time.

• It should be well defined

• It should be easily reproduced.