|
|
Do you want 100% Marks with less
effort? Then prepare the YSA Guess. Especially
designed for Karachi Board of Secondary Education (New
Pattern).
GUESS
PAPER
PHYSICS
PAPER-I
SECTION
"A" (MULTIPLE CHOICE QUESTIONS)
(17 MARKS)
NOTE
Attempt all questions
from this Section.
Q.1. Choose the correct
answer for each from the given options.
i. Which of the following was written by Ibn-ul-haitham?
a) Kitabul Manazir
b) Kitabul Qanoon Al-Masoodi
c) Al-Shifa
d) Qanun-Fit-Tib
ii. A projectile is thrown up with the initial velocity of
V0 making an angle of 30o with the horizontal direction. It
will cover the same range if the angle is
a) 15o
b) 20o
c) 45o
d) 60o
iii. A body of mass 10 kg starts falling freely. The height
lost by it in the first second is
a) 4.9m
b) 9.8m
c) 19.6m
d) 49m
iv. If a man goes to a height equal to the radius of the
earth from its surface, his weight relative to that of earth
would become.
a) half
b) same
c) twice
d) one-fourth
v. The dimensions of
angular momentum are
a. MLT-1
b) ML2T-1
c) M2LT1
d) MLT-2
vi. Which of the following is not the unit of power?
a) horse power
b) foot pound/sec
c) joule/sec
d) kilowatt-hour
vii. A mass connected by a spring is performing simple
harmonic motion with the time period 'T'. If we double the
mass of its block, the new time period will be
a) T
b) 0.70 T
c) 1.414 T
d) 2T
viii. Beats are the results of
a) Diffraction
b) Constructive
interference only
c) Destructive
interference only
d) Constructive and
destructive interference both
ix. When light (white) passes through thin films, colours
are formed due to
a) diffraction of light
b) dispersion of light
c) interference of light
d) both interference and
dispersion of light.
x. In Michelson's interferometer, semi-silvered plate is
used to obtain.
a) Dispersion
b) Phase coherence
c) Monochromatic light
d) Unpolarized
xi. Two convex lenses of the same focal length 'f' are kept
touching each other. The focal length of the combination
will be
a) f
b) f/2
c) 2f
d) 2f + 2
xii. The centre of mass of a system of particles
a) coincides with the
centre of gravity
b) does not coincide with
the centre of gravity
c) coincides with the
centre of gravity in the uniform gravitational field.
d) none of these
xiii. The angle between centripetal acceleration and
tangential acceleration is
a) ZEROo
b) 30o
c) 90o
d) 180o
xiv. If the velocity of a body is doubled, its kinetic
energy will be
a) doubled
b) four times
c) same
d) halved
xv. When a body slides over a surface the kinetic friction (fk)
and static friction (fs) are related as
a) fk < fs
b) fs < fk
c) fk = 0
d) fs = 0
xvi. If a vector is divided by its magnitude, the vector so
obtained is called
a) null vector
b) unit vector
c) position vector
d) free vector
SECTION
"B" (SHORT ANSWER QUESTIONS)
(40 MARKS)
Q.2 Answer any Ten questions from this section. All
questions carry equal marks.
i. Can the resultant of two vectors of the same magnitude be
equal to the magnitude of either of the vectors? How?
ii. Is it possible for a body to have an acceleration when
moving with a
a) constant velocity
b) constant speed
iii. If the tension in a string is doubled, what will be the
effect on the speed of standing waves in the string?
iv. Write down the expression for the acceleration
representing simple harmonic motion. Would you keep the
amplitude of a simple pendulum small or large? Why?
v. How did Thomas Young achieve the condition of Phase
Coherence for light in his double-slit experiment?
vi. A boy throws a ball vertically upward from the ground
with the velocity 25 m/s. On its way down it is caught 5 m
above the ground. How long did the trip take and with what
velocity was it coming down?
vii. A mortar shell is fired at a target 500 m away with the
velocity of 90 m/s calculate the maximum possible value of
the launch angle.
viii. At what depth from the surface of earth would the
acceleration due to gravity (g) be half on earth's surface?
ix. Calculate the speed of sound in air at 0oC if the mean
molar mass (M) for air is 0.0288 kg/mol, molar gas constant
(R) is 8.341 J/mol - K and y = 1.40
x. Calculate the length of second's pendulum on moon's
surface where acceleration due to gravity is 1.63 m/s2.
xi. If the radius of the 14th Newton's ring is 1 mm when the
light of wavelength 5.89 x 10-7 m is used what is the radius
of curvature of the layer surface of the lens used?
xii. The magnifying power of a simple microscope is 6:
calculate the focal length of its convex lens in centimetres.
xiii. A spring 4 m long resonates in four segments (node at
both ends). The frequency of the driving system on the
spring is 20 hertz, calculate the speed of the wave in the
spring.
xiv. How many fringes will pass a reference point if the
mirror of a Michelson's interferometer is moved by 0.08 mm,
the wavelength of light used is 5800Ao?
SECTION
"C" (DESCRIPTIVE ANSWER QUESTIONS)
(28 MARKS)
NOTE
Answer any Two questions
from this Section. All questions carry equal marks.
Q.3 (A) What is meant by Equilibrium? Define its types.
Explain the conditions of equilibrium with mathematical
expressions.
Q.3 (B) Describe the
construction and working of an Astronomical Telescope.
Derive the formula for its magnification with the help of a
ray diagram.
Q.4 (A) Explain Young's double-slit experiment and derive an
expression for fringe spacing with the help of a diagram.
Q.4 (B) Derive an
experiment for the instantaneous velocity of a body
performing simple harmonic motion. Prove that the total
energy of a simple harmonically moving body is constant.
Q.5 (A) What is Doppler Effect? Derive expressions for the
apparent frequency of a sound when:
i. an observer moves
towards a stationary source.
ii. the source moves
towards a stationary observer.
Q.5 (B) State Newton's
Law of Gravitation and discuss the variation of 'g' with
height OR depth.
|
|
|
