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Answer ALL Questions
1.Write True or False. (4- marks )
(a) Mass cannot be change by the location , shape and speed of the body.
(b) Different vector quantities like velocity and force cannot be added.
(c) Linear motion has only one direction.
(c) The centre of gravity is at 0.5 x102 cm mark for a uniform metre rule.
Fill in the blanks. (4- marks )
(a) Displacement is defined as the distance travelled along a _____ direction.
(b) Energy is the _____ to do work.
(c) The normal temperature is _____ ℉.
(d) The ice point is 0℃ in celsius scale and _____ K in kelvin scale.In the equation s =v0t + 1/2at2 ,s,v0 and a are magnitudes of the respective vector quantities.
Write down the equation in vector form.
A vector of magnitude 5 units is inclined at an angle 37° to the x axis . Find the magnitudes
of the vector components along x and y axis. ( 5- marks )Which of the following quantities are scalars and which are vectors?
(a) speed (b) velocity (c) average velocity (d) acceleration (e) displacement.
A particle starting from rest moves along a straight line with a constant acceleration of 2 ms-2.
What is the velocity of the particle 9 s after it started from rest? ( 5- marks )
SECTION (B)
Answer ALL Questions
Answer any FOUR Questions
(a) Is work a vector or scalar? Define “energy”. A wooden sphere of mass 0.15 kg is thrown
with a velocity of 30 ms-1 .Find the kinetic energy of the sphere. (4-marks )
(b) Define “work” . Write down the unit of work in SI system. A woman push a child, who is
riding a tricycle, with a 200N force. The tricycle moves a distance of 2m and the work done
by the woman is 100J. Find the angle between the force and the displacement. (4-marks )(a) Define speed and velocity such that the two may be distinguished. An object moves with
an initial velocity of 4ms-1 . If it moves with a uniform acceleration of 2ms-2 find the
displacement after 20 s. (4-marks )
(b) A body moving with a constant acceleration reach the velocity 4ms-1 after 10s. If the
body start from rest , find the velocity after (a) 12s (b) 14s (c) 16s (d) 18s. Draw the
velocity time graph for the interval 10 s to 18 s. From the graph , find the velocities at
8s and 20s. (4marks )
P.T.O →
(a) State law of conservation of momentum. ( 4 marks )
A 30g bullet moving at a constant velocity hits a wooden block of mass 3kg and continues
to travel at the velocity of 2 ms-1 together with the block. What is the velocity of the bullet
when it hits the block?
(b)A 0.2kg marble is at rest on a smooth table. Another marble of mass 0.1 kg moving at
a constant velocity of 10 ms-1 towards the east hits this marble and it recoils to the west
with the velocity of 5ms-1. Find the velocity of the marble which was at rest? ( 4 marks )(a) In order to weight a body in the laboratory, a uniform plank of wood AB 3 m long and
having a mass of 8kg is pivoted about a point 0.5 m from A. The boy stands 0.3m from A
and a mass of 2 kg is placed 0.5m from B in order to balance the plank horizontally .
Calculate the mass of the boy. ( 4 marks )
(b) A heat resistant glass at 15℃ is fully filled with 250 cm3 of glycerine . If the temperature
increases to 25℃ how much glycerine overflows? The coefficient of volume expansion of
glycerine is 5.1 x10-4K-1 and that of heat resistant glass is 0.09 x 10-4K-1. ( 4 marks )(a) According to observation and measurements the farthest galaxies are at a distance of
1026 m from the earth . When space travel become highly advanced do you think that man
will be able to visit those galaxies?(1 year ≃ 108s ) ( 4 marks )
(b) A man walks 2 mi east and then 3 mi i