Federal Board Class X Physics

SECTION “A”

Q.1. Insert the correct option.

i. If an object is placed in font of a convex lens between F and 2F what will the image be?

• Real an smaller in size
• Virtual and greater in size
• Real and greater in size
• Virtual and smaller in size

ii. In a P-type semi-conductor nearly whole of the current flows due to

• Electrons
• Holes
• Protons
• Positrons

iii. The engine of a bus moving on a road suddenly stops but continues its motion. What is it due to?

• Inertia
• Force
• Momentum
• Potential energy

iv. The liquids transmit external pressure equally in all directions. What is this phenomenon known as?

• Archimedes Principle
• Hooke’s Law
• Pascal’s Law
• Boyle’s Law

v. An observation recorded during an experiment was 0.04053cm. How many significant figures are there in it?

• 5
• 4
• 3
• 6

vi. What is the mechanical advantage of an inclined plane?

• h/l
• sin θ
• l/h
• R/r

vii. When strings of a catapult are pulled what type of energy is stored in it?

• Kinetic
• Gravitational Potential
• Elastic Potential
• Chemical Potential

viii. Amongst which is the unit of capacitance.

• Coulomb
• Volt
• Farad
• Watt

ix. What will the centripetal force become if velocity of a body moving on a circle is doubled?

• Two times
• Six times
• 1/2 times
• four times

x. Half life of krypton is 3.16 minutes. How much of 200g of it, will be left after 12.64 minutes?

• 50 gm
• 25 gm
• 12.5 gm
• 100 gm

xi. The shape of the lines of magnetic force in case of a straight current carrying conductor is

• Elliptical
• Triangular
• Circular
• Spherical

xii. The wave length of a wave passing through a medium is 0.2m. If wave speed is 4ms⁻¹, what is the frequency of the wave?

• 8 Hz
• 20 Hz
• 40 Hz
• 50 Hz

SECTION “B”

Q.2. Attempt any FOURTEEN parts.

i. What is the name of the Muslim scientist who worked in the field of optics? Describe any four of his discoveries.

ii. How can you say that the motion of a simple pendulum is simple harmonic? Explain briefly. Write the formula for finding the time period of a simple pendulum.

DIAGRAM

iii. Give two examples of derived units and explain how they are derived from base units.

iv. Before firing the momentum of a gun with a bullet is zero. How will you explain that momentum of the system remains zero when the gun is fired? Write the law of conservation of momentum.

v. When we beat a drum force fully a loud sound is produced. Explain why? Write names of the factors on which loudness of the sound depends.

vi. Electrostatic is being used in applying paints on the surface of different articles. This method is very effective and cheap. Explain why?

vii. The given graph represents distance ‘s’ covered by a car during time ‘t’.

a) What will be the distance covered after 7′s?
b) After how many seconds will the car cover a distance of 45m?
c) Write the scale used on the x-axis.

viii. Velocity of a car is 100 Kmh⁻¹ in the direction of 30o with the x-axis. Draw representative line of this velocity.

ix. A motorcycle is moving with a velocity of 72 Kmh⁻¹. Suddenly brakes are applied. If it covers a distance of 20 m before it shops them calculate the acceleration of the motorcycle.

x. What rules does D.C motor work on? Define the rule

xi. A player throws a ball of mass 400 g with a velocity of 30ms⁻¹. Find the kinetic energy of the ball.

xii. What is Ohm’s Law? Derive its equation.

xiii. Differentiate between force and power.

xiv. Differentiate between P-type and N-type semi-conductors. Give one example for each of the two. “Why does current easily flow through N-type material.”

xv. Define inertia. What is the unit of weight? Write its definition also.

xvi. Derive the formula for finding the heat absorbed or released by a body, on changing its temperature.

SECTION “C”

NOTE: Attempt any TWO questions.

Q.3. (a) What is an artificial satellite? Write two advantages of these satellites.
Q.3. (b) Derive the formula for the speed of an artificial satellite.
Q.3. (c) Define centripetal force.

Q.4. (a) Define uniform acceleration, velocity, rotator motion and displacement.
Q.4. (b) Prove the equation: 2as = V²f – V²i
Q.4. (c) A ball is thrown vertically upwards with a velocity of 40ms⁻¹. Determine the maximum height which the ball will attain and the time to reach the maximum height.

Q.5. (a) Copy the diagram on your answer sheet and point out.

DIAGRAM

i. Angle of deviation
ii. Angle of refraction
iii. Angle of incidence
iv. Refracted ray

Q.5. (b) Define the angle of minimum deviation, linear magnification and refractive index.
Q.5. (c) What is an optical fiber? Write three of its uses.