Copy Set-1 CP Star-2012 XII going [SAT+MAT] - Career Point

Q.13 In the arrangement shown in figure, the sleeve M
of mass m is fixed between two identical spring
whose combined force constant is k. The sleeve
can slide without friction over a horizontal bar
AB. The arrangement rotates with a constant
angular velocity ω about a vertical axis passing
through the middle of the bar. At what value of
ω will there be no oscillations of the sleeve ?
A
M
B
Q.13 fp=k esa n'kkZ;h O;oLFkk esa] m nzO;eku dh Lyho M
nks le:i fLizaxksa ftldk la;qä cy fu;rkad
k gS] ds e/; dlh xbZ gSA Lyho {kSfrt NM+ AB ds
Åij fcuk ?k"kZ.k ds fQly ldrh gSaA O;oLFkk fu;r
dks.kh; osx ω ls NM+ ds e/; ls xqtjus okyh m/oZ
v{k ds lkis{k ?kw.kZu djrh gSA ω ds fdl eku ij
Lyho nksyu ugha djsxh ?
A
M
B
(1) k < mω 2 (2) k < 2mω 2
m
(3) k =
2
ω
(4) None of these
Q.14 The earth receives solar energy at the rate of
2 cal cm 2 per min. Assuming the radiation to be
black body in character, estimate the surface
temperature of the sun. Given that σ = 5.67×10 –8
W/m 2 /K 4 and angular diameter of the sun = 32
min of arc.
(1) 3090 K (2) 5810 K
(3) 3260 K (4) 4150 K
Q.15 Seven identical rods of material of thermal
conductivity k are connected as shown in the
figure. All the rods are of identical length l and
cross-section area A. If the one end B is kept at
100ºC and the other end is kept at 0ºC, what
would be the temperatures of the junctions C, D
and E (θ C , θ D and θ E ) in the steady state ?
C k D
ω
(1) k < mω 2 (2) k < 2mω 2
m
(3) k =
2
ω
(4) buesa ls dksbZ ugha
Q.14 i`Foh 2 cal cm 2 izfr feuV dh nj ij lkSj ÅtkZ
izkIr djrh gSA lw;Z dks d`f".kdk ds :i esa ekurs
gq;s] lw;Z dh lrg dk rki ifjdfyr dhft;sA fn;k
x;k gS σ = 5.67×10 –8 W/m 2 /K 4 rFkk lw;Z dk
dks.kh; O;kl = 32 min of arc gSA
(1) 3090 K (2) 5810 K
(3) 3260 K (4) 4150 K
Q.15 izR;sd k Å"eh; pkydrk okys inkFkZ dh cuh lkr
le:i NM+ksa dks fp=kkuqlkj tksM+k x;k gSA lHkh NM+s
le:i yEckbZ l rFkk vuqizLFk dkV {ks=kQy A dh
gSA ;fn ,d fljs B dks 100ºC ij rFkk nwljs fljs
dks 0ºC ij j[kk tk;s] rks fu;r voLFkk esa lfU/k;ksa
C, D o E (θ C , θ D rFkk θ E ) ds rki D;k gksaxs ?
C k D
ω
k
k
k
k
k
k
k
k
A k E k
(1) θ E = 50ºC and θ D = 37.5 ºC
(2) θ E = 50ºC, θ C = 62.5ºC and θ D = 37.5ºC
(3) θ E = 50ºC, θ C = 60ºC and θ D = 40ºC
(4) None of these
B
A k E k
(1) θ E = 50ºC rFkk θ D = 37.5 ºC
(2) θ E = 50ºC, θ C = 62.5ºC rFkk θ D = 37.5ºC
(3) θ E = 50ºC, θ C = 60ºC rFkk θ D = 40ºC
(4) buesa ls dksbZ ugha
B
Space for rough work
CAREER POINT, CP Tower, Road No.1, IPIA, Kota (Raj.), Ph: 0744-3040000 Page # 5