### What is thermometry?

Thermometry The branch of heat relating to the measurement of the temperature of a body is called thermometry. The thermometer is an instrument used to measure the temperature of a body. The essential requisites of a thermometer are given as under:  1) Construction, 2) Calibration, and 3) Sensitiveness. For the construction of a thermometer, the proper choice of a substance, whose physical property varies uniformly with rising in temperature, is essential. 1) Construction The physical property of a substance plays an important role in the construction of a thermometer. In a mercury thermometer, the principle of expansion of mercury with rising temperature is used. The platinum resistance thermometer is based on the principle of the change in resistance with a change in temperature. The gas thermometer is based on the principle of change in volume or pressure with a change in temperature. 2) Calibration  When a thermometer is constructed, it should be properly calibrated. The standa

## 👉All Chapter Contents👈

• 2.1 Rest and Motion
• 2.2 Different Types of Motion
• 2.3 Scalar and Vector quantities
• 2.4 Distance and Displacement
• 2.5 Speed and Velocity
• 2.6 Acceleration and Deceleration or Retardation
• 2.7 Equation of Motion
• 2.8 Laws of Falling Bodies

## 2.1 Rest and Motion

• What is rest?
• What is motion?
• What is a position?
• What is a reference point?
• What do you understand by reference frame?
• All the rests and motion of the universe are relative, no motion is absolute, no absolute rest - explain.

• What is linear motion?
• What is circular motion?
• What is translational motion?
• What is periodic motion?
• What is oscillatory motion?
• What is simple harmonic motion?
• Explain all oscillatory motions are periodic motions but all periodic motions are not oscillatory motions.

• What is quantity?
• What is the normal body temperature?
• What is a scalar quantity?
• What is a vector quantity?
• Write the difference between scalar quantities and vector quantities.
• Work is a scalar quantity - explain.
• Explain the intensity of electricity as a vector quantity.

• What is distance?
• What is displacement?
• The movement does not depend on the direction of the object - explain.
• What do you mean by the movement of an object is 60 m southward.

• What is speed?
• What is the unit of speed?
• What is the dimension of speed?
• What is average speed?
• What is instantaneous speed?
• What do you understand by the speed of a car is 45 km/h?
• What is velocity?
• What is the unit of velocity?
• What is the dimension of velocity?
• What is average velocity?
• What is uniform velocity?
• What is unequal velocity?
• When can the velocity of an object be zero?
• Write the difference between speed and velocity.

• What is acceleration?
• What is the unit of acceleration?
• What is the dimension of acceleration?
• What is uniform acceleration?
• What is unequal acceleration?
• Acceleration due to gravity is called uniform acceleration - explain.
• What is deceleration or retardation?
• Gravitational acceleration is called uniform acceleration - explain.

• Write all the equation of motion.
Mathematical Problems:

## 2.8 Laws of Falling Bodies

• What is gravity?
• What is gravitation?
• What is acceleration due to gravity?
• What is falling body?
• Write the laws of falling bodies.
• What is the first law of falling bodies? Explain.
• What is the second law of falling bodies? Explain.
• What is the third law of falling bodies? Explain.
Mathematical Problems: