Question 2 :
State whether the given statement is True or False :The force on a mass m due to gravity is mg.

Question 3 :
The __________ of an object does not change from place to place.

Question 4 :
Helium is preferred over hydrogen for filling balloons because it is 

Question 5 :
The force acting on a mass of 1 g due to the gravitational pull on the earth is called 1 g-wt. One g-wt equals :

Question 8 :
How can you determine relative density of a substance using the Archimedes principle.<br/>

Question 9 :
If $S_{1}$ is the specific gravity of a solid with respect&#160;to a liquid and $S_{2}$ is the specific gravity of the&#160;liquid with respect to water, then the specific gravity&#160;of the solid with respect to water is :

Question 10 :
Is the buoyant force on a submerged object equal to the weight of the object itself or equal to the weight of the fluid displaced by the object?<br/>

Question 11 :
the density of cooking oil is $0.6g/c{m^3}$ What is the mass of $18c{m^3}$ of the cooking oil?

Question 13 :
A block of wood weights 12 kg and has a relative density 0.6. It is to be of its volume immersed. What weight of a metal is needed if the metal is on the top of wood? [Relative density of metal = 14].

Question 14 :
Two thin circular discs of radii $3 cm$ and $4 cm$ respectively are placed seperatly at the bottom of a vessel containing water. The ratio of thrusts,acting on them will be:<br/>

Question 15 :
On the earth, a Sumo of 420 kg is checking his reading on a spring balance. To have the same reading of spring balance on the moon, how many Sumos of mass 420 kg each should stand on it. Explain. (g = 30 m s$^{-2}$)<br>

Question 17 :
Assertion: If earth suddenly stops rotating about its axis, then the value of acceleration due to gravity will become same at all the places. Reason: The value of acceleration due to gravity is independent of rotation of earth.

Question 18 :
If the diameter of earth becomes two times its present value and its mass remains unchanged then how would the weight of an object on the surface of the earth be affected?

Question 19 :
A mass $M$ is split into two parts $m$ and $\left(M-m\right)$ which are then separated by a certain distance. The ratio ${m}/{M}$ which maximizes the gravitational force between the parts is

Question 20 :
Two metallic spheres, each of mass M, aresuspended by two strings each of length L. Thedistance between the lower ends of the strings isL. The angle which the strings make with thevertical due to mutual attraction of the spheres is<br>

Question 22 :
Students I, II and III perform an experiment for measuring the acceleration due to gravity (g) using a simple pendulum. They use different lengths of the pendulum and/or record time for different number of oscillations. The observations are shown in the following table. Least count for length = $0.1 cm$, Least count for time = $0.1s$.<br/><table class="wysiwyg-table"><tbody><tr><td>Student</td><td>Length of Pendulum (cm)</td><td>Number of Oscillations(n)</td><td>Total Time for n Oscillations (s)</td><td>Time Period (s)</td></tr><tr><td>I</td><td>&#160;64.0</td><td>8</td><td>128.0</td><td>16.0</td></tr><tr><td>II</td><td>64.0</td><td>4</td><td>64.0</td><td>16.0</td></tr><tr><td>III</td><td>20.0</td><td>4</td><td>36.0</td><td>9.0</td></tr></tbody></table>If $E_I, E_{II}, E_{III}$ are the percentage errors in g, i.e., $(\frac{\triangle g}{g}\times 100)$ for students I, II and III, respectively, then<br/>

Question 23 :
At a place, value of acceleration due to gravity $g$ is reduced by $2$% of its value on the surface of the earth (Radius of earth = $6400 \ km$). The place is:-

Question 24 :
Explorer $38$, a radio-astronomy satellite of mass $200$kg, circle the Earth in an orbit of average radius $\displaystyle \frac {3R}{2}$ where $R$ is the radius of the Earth. Assuming the gravitational pull on a mass of $1$kg at the earth's surface to be $10 N$, calculate the pull on the satellite