1. Choose the correct answer for each from the given options: (17)
(i) The Laws of Reflection were first introduced by:
(ii) In S.I System the unit of mass is:
(iii) A 25 N force, acts along the X-axis, its Y-component is:
(iv) The acceleration of a ball thrown vertically upward will, in S.I. system, be;
(v) A body will be in a state of stable equilibrium if its center of gravity lies
(vi) The mass of the earth is:
(vii) The S.I. unit of work is:
(viii) For an ideal machine:
(ix) The pressure of a liquid depends:
(x) The maximum density of pure water is at:
(xi) Sound waves cannot travel through:
(xii) A virtual, erect and diminished image is always obtained from a:
(xiii) The speed of light in a vacuum is
(xiv) If I= 1.5-amps, R = 10 ohms, then V is:
(xv) Shunt converts a galvanometer into:
(xvi) The reflection is obtained from a:
(xvii) Gamma rays are:
Note: Answer 14 questions from this section.
2. Define any three branches of Physics.
3. Two forces of 3N and 4N are acting on a body. If the angle between them is 90°, find the magnetic of the resultant vector.
4. If Fx, Fy are the horizontal and vertical components of a vector F, write down the formulae for the magnitude and direction of F. Show Fx, Fy, and F by a diagram
5. A car moving with a uniform acceleration attains a speed of 36km/hr in 2 minutes; find the acceleration of the car
6. Write down three methods of reducing friction
7. Define Linear Momentum. Write down its formula and S.I unit.
8. Define Equilibrium. Write down the conditions of equilibrium and the relate formulae.
9. A stone of 200 gm mass tied to one end of a string of length 50 cm is whirled from the other end in a circle with the constant speed of 2 m/s; find the tension in the string.
10. The length of the handle of a Screw Jack is 42cm and its pitch 1.001m; find its Mechanical Advantage.
11. State Pascal’s Principle. Describe any one of its application.
12. 117.6 J heat is required to raise the temperature of 10gm of silver by 50°C to find the specific heat of silver
13. Define the following: (i) Echo (ii) Ultrasonic wave (iii) beats
14. Define the following: (i) Irregular Reflection (ii) Radius of Curvature (iii) Magnification of a Concave Mirror
15. A convex lens forms a virtual image of an object placed 5cm away from the optical centre at a distance of 10cm. Determine the focal length of the convex lens.
16. Define: (i) Photon (ii) Dispersion of Light (iii) Total Internal Reflection
17. What is the Wave Theory of Light? Write down two phenomena which support this theory.
18. A force of 50N acts on a body. If the moment arm is 0.5m, find the value of the Torque.
19. A 100-watt bulb operates in a 220v circuit; find the current through the bulb.
20. What is an Electromagnet? Illustrate it with a labeled diagram and write down its two uses.
21. Define Reflection. Describe the working of a semiconductor diode as a rectifier.
22. Write down 3 precautions to minimize radiation hazards
NOTE: Attempt 2 questions from this section. (26)
23.(i) Derive the equation 2a S = v; -V;2
(ii) Write down two characteristic properties of Simple Harmonic Motion.
(iii) The frequency of vibration of a wire is 200 hertz; find its time period.
(iv) Write down four similarities between electrostatic induction and magnetism.
24.(i) Define Evaporation. Write down any four factors on which the rate of evaporation depends.
(ii) Define Kinetic Energy and Potential Energy and write down 2 points of difference between them.
(iii) Draw ray diagrams only to show the nature, position and size of the images formed by a concave mirror when the object is placed:
(a) at the centre of curvature of the mirror.
(b) between the centre of curvature and the principal focus
25(i) What is natural radioactivity? Write down four properties of Alpha rays.
(ii) Define the following:
(a) Refractive Index -(b) Critical Angle
(c) Power of a Lens (d) Magnifying Glass
(iii) What is an electric capacitor? Write down three factors upon which its capacity depends.