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G10, Physics First Semester Test Time Allowed (45)minutes
Answer All Questions

1. Fill in the blanks. (5 marks)
   (1) The unit of gravitational constant is ………. .
   (2) A unit vector has the magnitude of ………. unit.
   (3) Since displacement has both magnitude and direction, displacement is a ………. quantity.
   (4) 1 dyne force acting horiz ………. .
2. Is work a vector or scalar? A child pulling a toy car with a 10N force. The direction of the force makes an
   angle of 20° with the horizontal plane. If the car moves 6 m, how much work does the child do?
   3.Express the units of area expansion and volume expansion. A heat resistance glass at 15℃ is fully filled
   with 250 cm3 of glycerine. If the temperature increase to 25 ℃ how much glycerine overflows? The
   coefficient of volume expansion of glycerine is 5.1 x 10-4K-1 and that of heat resistance glass is
   0.09 x 10-4K-1.
3. A 30 g bullet moving at a constant velocity hits a wooden block of mass 3 kg and continues to travel
   at a velocity of 2 ms-1 together with the block.What is the velocity of the bullet when it hits the block?
4. Rewrite the relation m (v-v_0)/t αF in vector notation. A 3 ton car moving with the velocity of 30 mi h-1 is
   brought to stop in 2 s. Find the resisting force of the brakes acting on the car.