Phy – Obj

1 CEEBCDEBCA

11 DECBCABDEE

21 ADACDCDEAB

31 BDBDDCBAAA

41 DBEACCBDED

51 CBCCDECCCA

physics- Ans

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section B answer 4 only

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12 a)

i ) It’ s weight

ii ) The upthrust of the fluid to which it fluts

12 bi )

Draw a table

Under Fundamental quantites :

– Velocity

– Time

Under derived quantity:

– Density

– Electric current

12 bii )

i ) Reducing the contact between the surfaces.

ii ) Application of grease

12 ci)

a=15 / 4

a=3 . 75m / 5 ^ 2

12 cii )

total distance travelled

j =ut + 1 / 2

a+ 2 =0 *4 + 1 / 2 * 3 . 75 *( 4 )^2

0 + 1 / 2 *3 . 75* 8

a=30 m / s

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section A answer 6 only

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1 ai)

– Regular maintenance is essential to keep machines and the work environment safe and reliable .

– It helps to eliminate workplace hazards .

1 aii )

Electrolysis can be used for electroplating of metals . expand in length by a fraction

1 b )

I =m / zt=0 . 0015 / 3 . 3 *10 ^ – 7 * 2400

I =0 . 0015 / 3 . 3 * 10^ – 7 *24 * 10^ 3

I =0 . 0015 / 7 . 92 * 10^ – 4

I =1 . 5 * 10 ^ – 3 / 7 . 92* 10^ – 4

I =0 . 19 *10 ^ 3 + 4

I =0 . 19 *10

I =1 . 9

I =0 . 7 A

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2 )

radius =5 m

acceleration =1200 m ^ 2

from a=v ^ 2 / r

v ^ 2 = 9 * r

v ^ 2 = 1200 *5

v ^ 2 = 6000

v =sqr 6000

v =77 . 46 m / s

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3 a)

A couple is a pair of forces , equal in magnitude , oppositely directed , and displaced by perpendicular distance or moment .

3 b )

i ) The forces exerted by one ‘ s hand on a screw -driver

ii ) The forces exerted by the tip of a screw- driver on the head of a screw

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7 a)

critical angle is the angle of incidence beyond which rays of light passing

through a denser medium to the

surface of a less dense medium

are no longer refracted but totally

reflected .

7 b )

– Light travels as transverse waves and can travel through a vacuum .

– Sound travels as longitudinal waves and needs to travel through a solid , liquid or gas .

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8 a)

i ) wrapping the coil around an iron core .

ii ) adding more turns to the coil .

iii ) increasing the current flowing through the coil .

8 b )

i ) plate area

ii ) Plate spacing

iii ) Dielectic material

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10 a)

Tabulate

– Solids

i ) they dont move around

ii ) they are rigid and dont flow

– Liquids

i ) liquids slosh around

ii ) the maintain the shape of their container

10 b )

diffusion

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