TEST SERIES FOR AIPMT (HALF SYLLABUS) - Career Point

Q.29 Two particles of mass m each are tied at the ends
of a light string of length 2a. The whole system is
kept on a frictionless horizontal surface with the
string held tight so that each mass is at a distance
a from the centre P (as shown in the figure).
Now, the mid point of the string is pulled
vertically upwards with a small but constant force
F. As a result, the particles move towards each
other on the surface. The magnitude of
acceleration, when the separation between them
becomes 2x, is:
F
m
P
m
a a
F
(1)
2m a
2 2
a − x
F
(2)
2m x
2
a − x
(3)
F
2m
x
a
(4)
F
2m
2
a − x
x
Q.30 A 3hp motor requires 2.4 kW to drive it; its
efficiency is about:
(1) 90% (2) 75% (3) 60% (4) 50%
Q.31 If the potential energy of a gas molecule is
M N
U = − 6 12
r r
, M and N being positive constants,
then the potential energy at equilibrium must be:
(1) zero
2
M
(2)
4N
2
N
(3)
4M
(4)
2
MN
Q.32 A force of (5 + 3x) N acting on a body of mass
20 kg a long the x-axis displaces it from x = 2m
to x = 6m. The work done by the force is:
(1) 20 J (2) 48 J
(3)68 J (4) 86 J
4
2
2
Q.29 nks d.k izR;sd m nzO;eku ds] 2a yEckbZ dh ,d
gYdh Mksjh ds fljksa ij ca/ks gSA lEiw.kZ fudk; ,d
?k"kZ.k jfgr {kSfrt lrg ij bl izdkj j[kk gS] fd
Mksjh dlh jgs rkfd izR;sd nzO;eku] dsUnz P ls a
nwjh ij jgsA (fp=kkuqlkj)A vc Mksjh ds e/; fcUnq
dks Å/okZ/kj Åij dh vksj ,d NksVs ijUrq fu;r
cy F ds lkFk [khapk tkrk gSA ifjek.kLo#i d.k
lrg ij ,d nwljs dhs vksj xfr djrs gSA Roj.k
dk ifjek.k tc muds e/; dh nwjh 2x gks] gS&
m
P
m
a a
F
(1)
2m a
2 2
a − x
F
(2)
2m x
2
a − x
CAREER POINT, CP Tower, Road No.1, IPIA, Kota (Raj.), Ph: 0744-3040000 Page # 7
(3)
F
2m
x
a
F
(4)
F
2m
2
a − x
x
Q.30 ,d 3hp dh eksVj dks pykus ds fy, 2.4 kW
vko';d gS] rks bldh n{krk yxHkx gS&
(1) 90% (2) 75% (3) 60% (4) 50%
Q.31 ;fn ,d xSl v.kq dh fLFkfrt ÅtkZ
M N
U = − 6 12
r r
gS] M rFkk N /kukRed fu;rakd gS]
rc lkE; ij fLFkfrt ÅtkZ gksxh&
(1) 'kwU;
2
M
(2)
4N
2
N
(3)
4M
(4)
2
MN
Q.32 20 kg dh ,d oLrq ij (5 + 3x) N dk ,d cy
x-v{k ds vuqfn'k dk;Z dj jgk gSA ;g bls
x = 2m ls x = 6m rd foLFkkfir dj nsrk gSA cy
}kjk fd;k x;k dk;Z gS&
(1) 20 J (2) 48 J
(3)68 J (4) 86 J
4
2
2