Answer: c (6)
A geostationary satellite orbits around the earth in a circular orbit of radius 36000 km. Then, the time period of a satellite orbiting a few hundred kilometres above the earth’s surface (REarth = 6400 km ) will approximately be (a) 1/2 …
(a) 64.5 (b) 129 (c) 182.5 (d) 730 Answer: b (23)
A projectile is projected with velocity kve in vertically upward direction from the ground into the space. (ve is escape velocity and k<1) . If air resistance is considered to be negligible then the maximum height from the centre of …
Two bodies of masses m1 and m2 are initially at rest at infinite distance apart. They are then allowed to move towards each other under mutual gravitational attraction. Their relative velocity of approach at a separation distance r between them …
(a) The gravitational force due to this object at the origin is zero (b) The gravitational force at the point B (2, 0, 0) is zero (c) The gravitational potential is the same at all points of the circle y2+ …
(a) mgR (b) 1/2 mgR (c) 2 mgR (d) 1/4 mgR Answer: b (251)
An artificial satellite moving in a circular orbit around the earth has a total (kinetic + potential) energy E0. Its potential energy is (a) – E0 …
A simple pendulum has a time period T1 when on the earth’s surface and T2 when taken to a height R above the earth’s surface, where R is the radius of the earth. The value of T2/T1 is (a) 1 …
(a) g will increase (b) g will decrease (c) Escape velocity will remain unchanged (d) Potential energy will remain unchanged Answer: Answer: (b,c,d) (9)
In order to make the effective acceleration due to gravity equal to zero at the equator, the angular velocity of rotation of the earth about its axis should be (g= 10 ms-2 and radius of earth is 6400 kms) (a) …
An inverted bell lying at the bottom of a lake 47.6 m deep has 50 cm3 of air trapped in it. The bell is brought to the surface of the lake. The volume of the trapped air will be (atmospheric …
2. Two bodies are in equilibrium when suspended in water from the arms of a balance. The mass of one body is 36 g and its density is 9 g / cm3. If the mass of the other is 48 …
(a) Decrease by 2% (b) Remain unchanged (c) Increase by 2% (d) Increase by 1% Answer: c (5)
Suppose the gravitational force varies inversely as the nth power of distance. Then the time period of a planet in circular orbit of radius R around the sun will be proportional to (a) R(n+1/2) …
(a) 1/3 (b) 1/2 (c) 1/4 (d) 1/5 Answer: b (6)
(a) The acceleration of S is always directed towards the centre of the earth (b) The angular momentum of S about the centre of the earth changes in direction but its magnitude remains constant (c) The total mechanical energy of …
(a) 0.7 (b) 0.2 (c) 0.1 (d) 0.5 Answer-a (9)
(a) 4 times (b) 1/4 times (c) 3 times (d) 1/3 times Answer-d (6)
(a) 3/4 (b) 4/3 (c) 1 (d) 5/3 Answer-b (4)
(a) Young’s modulus (b) Shear modulus (c) Modulus of rigidity (d) Bulk modulus Answer-d (12)
The specific heat at constant pressure and at constant volume for an ideal gas are Cp and Cv and its adiabatic and isothermal elasticities are EΦ and Eθ respectively. The ratio of EΦ to Eθ is (a) Cv/ Cp (b) Cp …
(a) γ×density (b) γ×volume (c) γ×pressure (d) γ×specific heat Answer-c (22)
(a) Density (b) Volume (c) Pressure (d) Specific heat Answer-c (7)
(a) L=10cm ,D=1mm (b) L=100cm ,D=2mm (c) L=200cm ,D=3mm (d) L=300cm ,D=4mm Answer-b (5)
(a) + 0.50 (b) – 0.50 (c) 0.25 (d) – 0.25 Answer-b (11)
(a) –1 to 1/2 (b) -3/4 to -1/2 (c) -1/2 to 1 …
A rubber cord 10 m long is suspended vertically. How much does it stretch under its own weight (Density of rubber is 1500 kg/m3, Y = 5×108 N/m2, g = 10 m/s2) (a) 15×10–4 m (b) 7.5×10–4 m …
A substance breaks down by a stress of 106 N/m2. If the density of the material of the wire is 3×103 kg/m3, then the length of the wire of the substance which will break under its own weight when suspended …
A wire of cross section 4 mm2 is stretched by 0.1 mm by a certain weight. How far (length) will be wire of same material and length but of area 8 mm2 stretch under the action of same force (a) …
A wire of length 2 m is made from 10 cm3 of copper. A force F is applied so that its length increases by 2 mm. Another wire of length 8 m is made from the same volume of copper. …
In the Young’s experiment, If length of wire and radius both are doubled then the value of Y will become (a) 2 times (b) 4 times (c) Remains same (d) Half Answer-c (17)
(a) Zero (b) Infinity (c) 1×1010 N/m2 (d) 10×1010 N/m2 Answer-b (13)
(a) 500 N (b) 1000 N (c) 10000 N (d) 4000 N Answer-d (11)
(a) -∞ to +∞ (b) 0 to 1 (c) -∞ to 1 (d) 0 to 0.5 Answer-d (11)
The magnitudes of the gravitational force at distances r1 and r2 from the centre of a uniform sphere of radius R and mass M are F1 and F2 respectively. Then Answer: A (12)
Imagine a light planet revolving around a very massive star in a circular orbit of radius R with a period of revolution T. If the gravitational force of attraction between planet and star is proportional R-(5/2)to , then T2 is proportional …