Group –A
Attempt all question (11x1 = 11)
1. Plank’s constant has the dimension of
a. Energy
b. mass
c. frequency
d. angular momentum
2. A car of mass m has an engine which cal deliver power P. The minimum time in which the car can be accelerated from rest to a speed V is
a. mv2 / 2P
b. Pmv2
c. 2Pmv2
d. mv2 P
3. The maximum velocity with which a car driver must traverse a flat curve of radius 150m and coefficient of friction 0.6 to avoid skidding is
a. 60
b. 30
c. 15
d. 25
4. An artificial satellite moving in a circular orbit at a distance h from the centre of the earth has a total energy E0. Its potential energy is
a. –E0
b. 1.5 E0
c. E0
d. 2E0
5. The Young’s modulus of the material of the wire is 2x1010 Nm-2 . If the elongation strain is 1%, then the energy stored in the wire per unit volume in Jm-3 is
a. 106
b. 108
c. 2x106
d. 2x108s
6. An electric cable of copper has just one wire of radius 9mm. It’s resistance is 5Ω. This single copper wire of cable is replace by six different well insulated copper wires each of radius 3mm. The total resistance of the cable now be equal to
a. 7.5Ω
b. 45Ω
c. 90Ω
d. 270Ω
7. Focal length of convex mirror is 30cm. if image is 5 times magnified. Then object distance will be?
a. 30cm
b. 36cm
c. 40cm
d. 50cm
8. The refractive index of glass is 1.5 and water is 1.33. Then what is the critical angle for glass water interface
a. 54.60
b. 480
c. 62.730
d. 560
9. An equilateral prism having angle 600 has refractive index 2 . what is the angle of incident for minimum angle of deviation?
a. 750
b. 00
c. 450
d. 600
10. The effective power in diopter if lenses of focal length +10 cm and -20cm are combined is
a. +5
b. -5
c. +3
d. -2
11. The quark combination of proton is,
a. udd
b. uud
c. uuu
d. ddd
Group –B
Answer the following question (8x5 = 40)
Q.1. a) Under what condition the sum of two equal vectors is equal to either of them?
b) Find the magnitude and direction of resultant for triangle law of vector addition.
OR
a) Why astronauts in a space capsule orbiting the earth experience a feeling of weightlessness?
b) Derive the relation for gravitational potential at a point due to a point mass.
Q.2. a) Define specific heat capacity of a substance.
b) Describe the method of mixture to measure the specific heat capacity of a solid.
Q.3. a) calculate reduce radiating power if the absolute temperature of a radiating body is suddenly halved?
b) Describe Searle’s method of determination of thermal conductivity of good conductor.
Q.4. a) Define root mean square speed of gas. Derive the expression for it.
b) Calculate the initial temperature, if pressure of a gas contained in a closed vessel is increased by 0.4% when heated by 10 .
Q.5. a) Derive expression for the focal length of Lens maker.
b) What is the apparent position of an object below a rectangular glass slab of refractive index 1.45 and the thickness 0.06m if a layer of water 0.005m thick is on the top of the glass slab?
Q.6. a) Using gauss’s theorem derive an expression for electric field outsides the charge spherical conductor.
b) What distance must an electron move in a uniform potential gradient 200 V/cm in order to gain kinetic energy 3.2x10-18 J?
Q.7. a) Find the equivalent capacitance of two capacitor when they are in i) series and ii) parallel b) three capacitors, each of capacity 6𝜇F are connected in series and are also connected in parallel with series combination of three capacitors 2 𝜇F , 4 𝜇F and 2 𝜇F. Calculate resultant capacitance.
Q.8. a) what do you mean by electric power?
b) Eight cells, each of emf 1.5v, are connected in series. If a current of 3A flows through an external resistance of 2Ω, calculate internal resistance of a cell.
Group –C
Give long answer to the following questions.( 8x3 =24)
Q.9. a) Why does a heavy rifle not kick as strongly as a light rifle using same cartridges?
b) Prove that the total mechanical energy in gravitational field is always conserved.
c) Suppose you try to move a crate by trying a rope around it and pulling on the rope at an angle 300 above the horizontal. What is the tension required to keep the crate moving with constant velocity? Assume weight of crate W= 500N and coefficient of dynamics friction is µk = 0.4.
Q.10 a) Why road are banked?
b) Derive an expression for the time period of oscillation of conical pendulum.
c) A certain string breaks when a weight of 25N acts on it. A mass of 500g is attached to one end of the string of 1m long and is rotated in a horizontal circle. Find the greatest number of revolutions per minute which can be made without breaking the string.
Q.11. a) What are energy band in solid?
b) How much energy is released during nuclear fission reaction?
c) Calculate the mass defect, binding energy and binding energy per nucleon of 26fe56. (Given, mass of proton = 1007276 amu, mass of neutron = 1.008665 amu, mass of 26fe56 = 55.934939amu).