Question

Q1 Name the four basic forces in nature. Arrange them in the order of their increasing strength
Q2 What are physical Quantities? Define fundamental unit. write seven fundamentals unit, with unit and Dimension
Q3 Write characteristic of physical unit? what is coherent system of units. State the advantage of SI over other system of
Units
Q4 Define the following terms, Light year, Astronomical unit, parsec. Define 1 Chandra Shekhar limit, atomic mass unit
Q5 Explain how will you determine the radius of an atom by Avogadro’s hypothesis.
Q6(a) The frequency ‘n’ of vibration of a stretched strings depends upon (i)its length l (ii) its mass per unit length’ m’ (iii) the
Tension T in the string Obtain the expression for n dimensionally
(b) derive by the method of dimensions an expression for the volume of a liquid flowing out per second through a narrow
Pipe. Assume that the rate of flow of liquid depends on (i) the coefficient of viscosity ἡ of the liquid (ii) the radius’ r’
Of the pipe (iii) the pressure gradient (p/l) along the pipe Take K =π/8
Q7 (i)The value of G in C G S system is 6.67 x10-8 Calculate the value of G in SI system dimensionally
(ii) Find the value of 60 Joule Per minute on a system that has 100g ,100cm, & 1minute as the base units
Q8 State the principle of Homogeneity of Dimensions What is its basis? find the dimension of a/b & axb in the equation
F= a√x +bt2 where F is force, x is distance & t is time
Q9 In successive measurements the readings of the period of oscillation of a simple pendulum were found to be 2.63s, 2.56s,
2.42s, 2.71s, & 2.80s in an experiment. Calculate (i) mean value of the period of oscillation (ii) absolute error in each
Measurement (iii) Mean absolute error (iv) relative error (v) percentage error (vi) express the result in proper form
Q10 (a) Find the relative error in Z, if Z = A4 B1/3 /C D3/2 . A physical quantity X = a2b3/c√d if the % errors of measurement in
a , b , c & d are 2%, 1% , 3% & 4% respectively then calculate the % error in X
(b) calculate focal length of a spherical mirror from the following observations Object distance u = (50.1±0.5) cm & image
Distance v= (20.1±0.2) cm

Answer 1

Answer:

(2) To describe events (natural or manmade) few concepts or words are required such words are called physical quantity.Units of fundamental quantities are called fundamental unit.

distance:(m)

mass:(kg)

time:(t)

electric current:(ampere)(a)

temperature:(kelvin K)

amount of substance:(mole)(mol)

luminous intensity:(candela)(cd)