Here we are giving model questions from Physics for EAMCET entrance examination of Andhra Pradesh. The candidates appearing for EAMCET can use these questions for practice.
1. When there is no external force acts on a system of particles the velocity of centre of mass of the system.
1) zero 2) constant 3) increases 4) decreases
3. Two identical thin uniform rods each of length L are joined to form ‘T’ shape. The distance of centre of mass of the combined system
from the point of contact or joint is
1) L/2 2) L/4 3) 3L/4 4) L
4. A boat of mass 300 kg and length 11m is at rest in still water. If a boy of mass 30kg walks from one end to the other, the distance
through which the boat moves is (neglect the resistance of water)
1) 1 m 2) 1.5 m 3) 3 m 4) Zero
13. If the density of a thin rod of lenght L varies with the distance X from one end as ρ = ρo(x2/l2), the position of centre of mass of rod from one end is
1. l/4 2. l/2 3. 3l/4 4. 3l/2
14. A uniform disc of radius of R is put over another uniform disc of radius 2 R of same thickness and density. If the peripheries of
the two discs tough each other, the distance of centre of mass at the system from the centre of the larger disc toward the centre
of the smaller disc is
1. R/5 2. R/10 3. 2R/5 4. 3R/5
16. Match the following
List-I List-II
a) The centre of mass of a e) zero system does not depend on
b) Sum of moments of f) constant masses of a system about
the centre of mass will
c) when there is no external g) uniform force acts on a system gravitaits velocity -tional field
of centre of mass
d) The centre of mass and h) frame of centre of gravity reference
coincide in
1) a-e, b-f, c-g, d-h
2) a-h, b-g, c-f, d-e
3) a-e, b-h, c-g, d-f
4) a-h, b-e, c-f, d-g
KEY
1)2 2)2 3)1 4)3 5)1 6)4.