MODEL GRAPH x y T (N) l (cm2) Relation between tension T (N) and length l (cm2) OBSERVATIONS Frequency of the tuning fork = Hz Variation of resonant length with tension UNIT- (XI- - ) PRACTICAL FIRST UNIT- (XI- - ) PRACTICAL FIRST - - - - Practical Sl.No. Mass M (kg) Tension T=Mg (N) Vibrating length l (m) l CALCULATION Calculate the value l for the tension applied in each case. RESULT • The resonating length varies as square root of tension for a given frequency of vibration of a stretched string. • l is found to be a constant.
UNIT- (XI- - ) PRACTICAL FIRST UNIT- (XI- - ) PRACTICAL FIRST - - - - SOME IMPORTANT CONSTANTS IN PHYSICS Name Symbols Value Speed of light in vacuum c . × m s - Gravitational constant G . × - N m kg - Acceleration due to gravity (sea level, at ° latitude) g . m s - Planck constant h .
× - J s Boltzmann constant k . × - J K - Avogadro number N A . × mol - Universal gas constant . J mol - K - Stefan – Boltmann constant σ .
× - W m - K - Wien’s constant b . × - m K Permeability of free space μ π × - H m - Standard atmospheric pressure atm . × Pa