División por Párrafos en las Traducciones Modernas ()
TÓPICO ESPECIAL: LA EDAD I. Introducción
16. As we go from the equator to the poles, the value of g ...
(A ) Remains constant (B) Decreases (C) I ncreases (D) Decreases upro latitude of 45o
17. If R is the radius of the earth and g the acceleration due to gravity on the earth’s surface, the mean density of the earth is = ...
(A) 4G
/
3gR (B) 3R/
4gG (C) 3g/
4RG (D) RG/
12g18. The radius of the earth is 6400 km and g=10ms-2. In order that a body of 5 kg weights zero at the equator, the angular speed of the earth is = ... rad/sec
(A) 1/80 (B) 1/400 (C) 1/800 (D) 1/600
19. The time period of a simple pendulum on a freely moving artificial satellite is ... sec
(A) 0 (B) 2 (C) 3 (D) Infinite
20. A spherical planet far out in space has mas Mo and diameter Do. A particle of m falling near the surface of this planet will experience an acceleration due to gravity which is equal to
(A) 2 0/ GM Do (B) 4mGMo Do/ 2 (C) 2 4GMo Do/ (D) 2 / GmMo Do 21. A body weights 700 g wt on the surface of earth How much it weight on the surface of planet
whose mass is 1/7 and radius is half that of the earth
(A) 200g wt (B) 1400g wt (C) 50 g wt (D) 300g wt. 22. The value of g on he earth surface is 980 cm/sec2. Its value at a height of 64 km from the
earth surface is ... cm5–2
23. If earth rotates faster than its present speed the weight of an object will. (A) increases at the equator but remain unchanged of the poles.
(B) Decreases at the equator but remain unchanged at poles. (C) Remain unchanged at the equator but decreases at poles. (D) Remain unchanged at the equator but increases at the poles.
24. The moon’s radius is 1/4 that of earth and its mass is 1/80 times that of the earth. If g represents the acceleration due to gravity on the surface of earth, that on the surface of the moon is ...
(A) g/4 (B) g/5 (c) g/6 (D) g/8
25. The depth of at which the value of acceleration due to gravity becomes 1/n the time the value of at the surface is (R = radius of earth)
(A) R/n (B) (n 1) n R (C) R/n2 (D) 1 n R n
26. If the density of smalll planet is that of the same as that of the earth while the radius of the planet is 0.2 times that of lthe earth, the gravitational acceleration on the surface of the planet is ...
(A) 0.2g (B) 0.4g (c) 2g (D) 4g
27. If mass of a body is M on the earth surface, than the mass of the same body on the moon surfae is
(A) M/6 (B) 56 (C) M (D) None of these 28. An object weights 72 N on the earth. Its weight at a height R/2 from earth is = ... N
(A) 32 (B) 56 (C) 72 (D) zero
29. If the radius of earth is R then height ‘h’ at which value of ‘g’ becomes one - fourth is
(A) R/4 (B) 3R/4 (C) R (D) R/8
30. If the mass of earth is 80 times of that of a planet and diameter is double that of planet and ‘g’ on the earth is 9.8 ms-2 , then the value of ‘g’ on that planet is = ... ms-2
(A) 4.9 (B) 0.98 (c) 0.49 (D) 49
31. Assuming earth to be a sphere of a uniform density, what is value of gravitational acceleration in mine 100 km below the earth surface = ... ms-2
(A) 9.66 (B) 7.64 (C) 5.00 (D) 3.1
32. Let g be the acceleration due to gravity at earth’s surface and k be the rotational K.E. of earth suppose the earth’s radius decreases by 2% keeping alt other quantities same then
(A) g decreases by 2% and K decreases by 4 % (B) g decreases by 4% and K increases by 2% (C) g increases by 4% and K increases by 4% (D) g decreases by 4% and K increases by 4%
33. A body weight 500 N on the surface of the earth. How much would it weight half way below the surface of earth
(A) 125N (B) 1250N (C) 500N (D) 1000N
34. The radii of two planets are respectively R1 and R2 and their densities are respectively 1 and 2 the ratio of the accelerations due to gravity at their surface is ...
(A) 1 2 12 22 1 2 : . g g R R (B) g g1: 2R R1 2:
1 2 : : g g R
R
g g: R
:R
35. At what height over the earth’s pole, the free fall acceleration decreases by one percent = ... km (Re = 6400 km).
(A) 32 (B) 80 (C) 1.253 (D) 64
36. Weight of a body is maximum at
(A) moon (B) poles of earth (C) Equator of earth (D) Center of earth 37. At what distance from the center of earth, the value of aceeleration due to gravity g will be
half that of the surfaces (R = Radius of earth)
(A) 2R (B) R (C) 1.414 R (D) o.414 R 38. The acceleration due to gravity near the surface of a planet of radius R and density d is proportional
to
(A) d/R2 (B) dR2 (C) dR (D) d/R
39. The acceleration due to gravity is g at a point distance r from the center of earth R. if r < R then
(A) g r (B) g r2 (c) g r-2 (D) g r-1
40. The density of a newly discoverd planet is twice that of earth. The acceleration due to gravity at the surface of the planet is equal to that at the surface of earth. If the radius of the earth is R, the radius of planet would be ...
(A) 2R (B) 4R (C) 1/4 R (D) ...
41. Density of the earth is doubled keeping its radius constant then acceleration, due to gravity will be ... ms-2(g = 9.8 ms2)
(A) 19.6 (B) 9.8 (C) 4.9 (D) 2.45
42. Weight of body of mass m decreases by 1% when it is raised to height h above the earth’s surface. If the body is taken to a depth h in a mine. change in its weight is
(A) 2% decreases (B) 0.5% decreases (C) 1% increases (D) 0.5% increases
43. If density of earth increased 4 times and its radius becomes half of then out weight will be... (A) Four times it present calue (B) doubled
(C) Remain same (D) halved
44. A man can jump to a height of 1.5 m on a planet A what is the height ne may be able to jump on another planet whose density and radius are respectively one- quater and one- third that of planet A
(A) 1.5 m (B) 15 m (C) 18 m (D) 28 m
45. If the value of ‘g’ acceleration due to gravity, at earth surface fis 10ms–2. its value in ms–2 at the center of earth, which is assumed to be a sphere of Radius ‘R’ meter and uniform density is (A) 5 (B) 10/R (C) 10/2R (D) zero
46. A research satellite of mass 200 kg. circles the earth in an orbit of avrage radius 3R/2 where R is radius of earth. Assuming the gravitational pull 10 N, the pull on the satellite will be =...N (A) 880 (B) 889 (C) 890 (D) 892
47. Acceleration due to gravity on moon is 1/6 of the acceleration due to gravity on earth. If the ratio of densities of earth e and moon m is e 53
m
then radius of moon Rm in terms
of Re will be ... (A) 5Re 18 (B) 1 Re 6 (C) 3 Re 16 (D) 1 Re 2 3
48. The acceleration of a body due to the attraction of the earth (radius R) at a distance 2R from the surface of the earth is = ...
(g = acceleration due to gravity at the surface of earth)
(A) g/9 (B) g/3 (C) g/4 (D) 9
49. The height at which the weight of a body becomes 1/16 th its weight on the surface of (radius R) is
(A) 3R (B) 4R (C) 5R (D) 15R
50. A spherical planet has a mass Mp and diameter Dp A particle of mass m falling freely near the surface of this planet will experience an acceleration due to gravity, equal to
(A) 2 4 GMp Dp (B) 2 GMpm Dp (C) 2 GMp Dp (D) 2 4GMpm Dp
51. Assuming the earth to have a constant density, point out which of following curves show the variation acceleration due to gravity from center of earth to points far away from the surface of earth ...
(D) None of these