It is very important to have the idea of any examination to get success in that. The best way to have that idea is to have a look at previous year Questions of that examination. That's why we have collected some previous year Questions with Solutions of JEE Main, JEE Advance, NEET, IIT JEE, AIEEE, AIIMS, WBJEE, EAMCET, Karnataka CET, CPMT, Kerala CET, MP PMT and Other State JE Exams so that you can get clear pattern and level of question that will be asked in forthcoming JEE Main, JEE Advance, NEET, IIT JEE, AIEEE, AIIMS, WBJEE, EAMCET, Karnataka CET, CPMT, Kerala CET, MP PMT and Other State JE Exams.
JEE Previous Year's Questions With Solutions
1. A block of mass M is pulled along a
horizontal frictionless surface by a rope of mass. If a force P is applied at
the free end of the rope, the force exerted by the rope on the block is: (AIEEE 2003)
(A) Pm/ (M – m)
(B) P
(C) PM/ (M + m)
(D) Pm/ (M + m)
Sol: (C)
Taking (Block + Rope) as a system:
Acceleration of the system, a = P/ (M + m)
FB,R = the force exerted by the rope on the block.
From the F.B.D. of the block:
→ Ma = FB,R
Or, FB,R = M * [P/ (M + m)]
Or, FB,R = PM/ (M + m).
2. A rocket with a lift- off mass 3.5 *
104 kg is blasted upwards with an initial acceleration of 10 m/s2.
Then the initial thrust of the blast is: (AIEEE
2003)
(A) 7.0 * 105 N
(B) 3.5 * 105 N
(C) 1.75 * 105 N
(D) 14.0 * 104 N.
Sol: (B)
Given: mass, m = 3.5 * 104 kg; acceleration, a = 10
m/s2.
→ Initial thrust, F = ma
Or, F = 3.5 * 104 * 10 = 3.5 * 105 N.
3. A light spring balance hangs from
the hook of the other light spring balance and a block of mass M kg hangs from
the former one. Then the true statements about the scale reads is: (AIEEE 2003)
(A) Both the scales read M/2 kg
(B) Both the scales read M kg each
(C) The scale of the lower one reads M kg and of the upper
one zero
(D) The reading of the two scales can be anything but the sum
of the reading will be M kg.
Sol: (B)
Both the scales read M kg each.
4. A machine gun fires a bullet of mass
40 g with a velocity 1200 m/s. The man holding it can exert a maximum force of
144 N on the gun. How many bullets can he fire per second at the most? (AIEEE 2004)
(A) Four
(B) Two
(C) Three
(D) One.
Sol: (C)
Given: mass of bullet, m = 40 g = 0.04 kg; final velocity, v
= 1200 m/; initial velocity, u = 0.
Let he can fire n bullets per second.
We have, Force = change in momentum per second
Or, 144 = n * 0.04 * (1200 – 0)
Or, n = 3.
5. Two masses m1 = 5 kg and
m2 = 4.8 kg tied to a string are hanging over a light frictionless
pulley. What is the acceleration of the masses when lift free to move? (AIEEE 2004, Odisha JEE 2002, UPSEAT 2002)
(A) 5 m/s2
(B) 0.2 m/s2
(C) 4.8 m/s2
(D) 9.8 m/s2.
Sol: (C)
The equation of motion of m1 = 5 kg:
→ m1g – T= m1a
Or, 5g – T = 5a ------- (1)
The equation of motion of m1 = 4.8 kg:
→ T – m2g = m2a
Or, T – 4.8g = 4.8a ------- (2)
Solving equation (1) and (2)
We get, a = 0.2 m/s2.
6. A block A of mass 7 kg is placed on
a frictionless table. A thread tied to it passes over a frictionless pulley and
carries a body B of mass 3 kg at the other end. The acceleration of the system
is (take g = 10 m/s2): (Kerala
CET 2001)
(A) Zero
(B) 3 m/s2
(C) 30 m/s2
(D) 10 m/s2
(E) 100 m/s2.
Sol: (B)
Let T be the tension in the string and a be the acceleration.
The equation of motion of A:
→ T = Ma
Or, T = 7a ------- (1)
The equation of motion of B:
→ Mg – T = Ma
Or, 3g – T = 3a ------- (2)
Solving equation (1) and (2)
We get, a = 3 m/s2.
7. A cricketer catches a ball of mass
150 g in 0.1 s moving with speed 20 m/s, then he experiences force of: (CBSE 2001)
(A) 0.3 N
(B) 3 N
(C) 30 N
(D) 300 N.
Sol: (C)
Given: mass of ball, m = 150 g = 0.15 kg; change of velocity,
ΔV = 200 – 0 = 200 m/s; time, t = 0.1 s.
We know, Force, F = ma
Or, F = 0.15 * 200/0.1 = 30 N
8. A body of mass 1 kg is falling with
an acceleration of 10 m/s2. Its apparent weight will be (g = 10 m/s2):
(MP PMT 2002)
(A) Zero
(B) 0.5 kg wt
(C) 2.0 kg wt
(D) 1.0 kg wt.
Sol: (A)
Given: mass, m = 1 kg; acceleration, a = 10 m/s2;
g = 10 m/s2.
Apparent weight, W’ = m (g – a)
Or, W’ = 1 * (10 – 10)
Or, W’ = 0.
9. A body whose mass is 50 kg stands on
a spring balance inside a lift. The lift starts to ascend with an acceleration
of 2 m/s2. The reading of the machine or balance (g = 10 m/s2):
(Kerala CET 2002)
(A) 60 kg
(B) 49 kg
(C) 50 kg
(D) 45 kg
(E) Zero.
Sol: (A)
Given: mass, m = 50 kg; acceleration, a = 2 m/s2;
g = 10 m/s2.
Apparent weight, W’ = m (g + a)
Or, W’ = 50 * (10 + 2)
Or, W’ = 600 N.
Now, W’ = m’g
Or, m’ = 60 kg.
10. A ball of mass 0.5 kg moving with a
velocity of 2 m/s strikes a wall normally and bounces back with the same speed.
If the time of contact between the ball and wall is 10– 3 s, the
average force exerted by the wall on the ball is: (Kerala CET 2002, Haryana CEET 2002)
(A) 5000 N
(B) 1000 N
(C) 1125 N
(D) 2000 N
(E) 500 N.
Sol: (D)
Given: mass, m = 0.5 kg; time, t = 10– 3 s; change
in velocity, ΔV = 2 – (–2) = 4 m/s.
Acceleration, a = ΔV/t = 4/10– 3 = 4 * 103
m/s2.
Force, F = ma = 0.5 * 4 * 103 = 2000 N.
11. You are on a frictionless horizontal
plane. How can you get off if no horizontal force is exerted by pushing against
the surface? (J&K CET 2002)
(A) By running on the plane
(B) By spitting or sneezing
(C) By jumping
(D) By rolling your body on the surface.
Sol: (B)
By spitting or sneezing.
12. A 1 kg particle strikes a wall with
velocity 1 m/s at an angle 300 and reflects at the same angle. If it
remains in contact with wall for 0.1 s, then the force is: (CBSE 2000, CPMT 2001)
(A) 10√3 N
(B) 30√3 N
(C) 40√3 N
(D) Zero.
Sol: (A)
Horizontal motion:
Change in velocity, ΔV = [(V cos 300) – (– V
cos 300)] = 2 * 1 * √3/2 = √3 m/s.
Acceleration, a = (√3)/ 0.1 = 10√3 m/s2.
Therefore, Force F = ma = 1 * 10√3 = 10√3 N.
13. A lift of mass 1000 kg which is
moving with acceleration of 1 m/s2 in upward direction, then the
tension developed in string which is connected to lift is: (CBSE 2002)
(A) 10800 N
(B) 11000 N
(C) 10000 N
(D) 9800 N.
Sol: (B)
Given: mass, m = 1000 kg; acceleration, a = 1 m/s2.
The equation of motion of lift:
→ ma = T – mg
Or, 1000 * 1 = T – 1000 * 10
Or, T = 11000 N.
14. A ball of mass 150 g moving with
acceleration of 20 m/s2 is hit by a force which acts on it for 0.1
s. The impulsive force is: (Punjab PMT
2003)
(A) 0.1 Ns
(B) 1.2 Ns
(C) 0.5 Ns
(D) 0.3 Ns.
Sol: (D)
Given: mass, m = 150 g = 0.15 kg; acceleration, a = 20 m/s2;
time, t = 0.1 s.
We know, Force = ma = 0.15 * 20 = 3 N.
Therefore, Impulse = Ft = 3 * 0.1 = 0.3 Ns.
15. Two masses M and M/2 are joined
together by means of light inextensible string passed over a frictionless
pulley as shown in figure. When the bigger mass is released, the small one will
ascend with an acceleration of: (Kerala
CET 2005)
(A) g/3
(B) g/2
(C) 3g/2
(D) g.
Sol: (A)
The equation of motion of M kg block:
→ Ma = Mg – T ------- (1)
The equation of motion of m1 = 4.8 kg:
→ Ma/2 = T – Mg/2 ------- (2)
Solving equation (1) and (2)
We get, a = g/3.
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