2018-10-01_Physics_For_You

Set 63

SINGLE OPTION CORRECT TYPE

1. In a vernier callipers 1 main scale division is 1 mm
   and there are 10 divisions on vernier scale which
   match with 9 divisions on main scale. When there
   is no object between the jaws (when they are in
   contact) the zero mark of the vernier scale is to the
   le of zeroth mark of main scale and 8th division of
   vernier scale coincided with one of the main scale
   divisions. When a plate is kept between the jaws
   zeroth mark of vernier scale crossed 12 mm mark
   on the main scale and vernier coincidence is 3. e
   correct thickness of the plate is
   (a) 121.1 mm (b) 12.5 mm
   (c) 13.1 mm (d) 11.5 mm


2. A block of mass 4 kg is
   placed on an another
   block of mass 6 kg which
   is placed on a rough
   horizontal surface as
   shown in the figure. m= 0.1

m= 0.8

6 kg

4 kg F

What maximum force that could be applied
on 4 kg block in horizontal direction so that
there is no relative slipping between the blocks?
(g = 10 m s–2)
(a) 46.6 N (b) 32 N (c) 42 N (d) 38.8 N

3. e system of mass A and B Shown in gure is
   released from rest from x = 0. Find maximum
   displacement of block B.

(a) 82 m (b) 42 m (c) 16 2m (d) 8 m

P

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4. A person is pulling a particle of mass m = 2 kg from
   ground on a xed rough hemispherical surface
   upto the top of the hemisphere with the help of a
   light inextensible string. Find the work done by the
   person. [R = 1, P = 0.5 and g = 10 m s–2]

m= 0.5

R= 1 m

(a) 10 J (b) 30 J (c) 25.5 J (d) 72 J

5. An isosceles triangle is to
   be cut from one edge of a
   square lamina of uniform
   mass density (as shown in
   the figure) such that the

l

P

h

l

remaining portion when suspended from the apex

P of the cut will remain in equilibrium in any

position. e value of h is

(a) ()22

2

− l (b) ()33

2

+ l

(c) ()33

2

− l (d) ()22

2

+ l

6. A particle is projected at time t = 0 from a point P
   on the ground with a speed v 0 , at an angle of 45° to
   the horizontal. Find the magnitude and direction
   of the angular momentum of the particle about P at
   time t = v 0 /g.

(a) −

mv

g

0

3

22

(b)

v

g

0

3

2

(c)

mv

g

0

2

(d)

v

g

0

2

22