Question 4 : Mass of a body changes at different places on earth. State whether true or false.

Question 5 : If the mass of a body is M on the surfrace of the&#160;earth, then its mass on the surface of the moon will be:<br/>

Question 6 : _______ of a body changes from place to place but its ______ remains constant.

Question 7 : When an object falls freely to the earth, the gravitational force acting on the body

Question 8 : Why does a mug full of water feel lighter inside water?<br>

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 : Assertion: Specific gravity of a fluid is a dimensionless quantity. Reason: It is the ratio of density of fluid to the density of water.

Question 12 : Assertion: A heavy object always falls faster than a light object when dropped from a height. Reason: Gravitational force is proportional to the mass of an object.

Question 13 : 60 cc&#160;of a liquid of relative density 1.4 is mixed with 40 cc of another liquid of relative density&#160;0.8. The density of the resulting mixture will be

Question 14 : A body is heated. What is the effect on its relative density?

Question 15 : Weight of a body is a scalar quantity. True or false.

Question 17 : The force with which the earth attracts a body is called its mass. True or false.

Question 18 : If the density of a metal is 8.2 g/cc, its relative density is.

Question 19 : The gravitational pull exerted by the earth on a body is called its:

Question 22 : An astronaut whose mass is 84 kg on earth will have a mass of approximately 14 kg on the moon.<br>

Question 23 : At the Earth, a block of mass $m$ &#10;which rest on the frictionless table,&#160; let $F$ be the force required to produce acceleration $a$. Calculate the force at the Moon to produce same acceleration if &#160;$g_{moon}$ is one sixth of $g_{earth}$.

Question 25 : What is the ratio of the gravitational pull of the sun on the moon to that of the earth on the moon?

Question 26 : When an object moves with a constant acceleration, under the influence of force of gravitation of the earth only, the object is said to have:

Question 27 : Buoyant force experienced by a solid is _____ the weight of the fluid displaced by it

Question 28 : A body is submerged in water. It is taken out and then submerged in mercury. What happens to its relative density with respect to the liquid in which it is submerged?

Question 30 : An object placed on a equal-arm balance requires 12 kg to balance it. When placed on a spring scale, the scale reads 12 kg. Everything (balance, scale, set of weights and object) is now transported to the Moon where the free-fall acceleration is one-sixth that on Earth. The new readings of the balance and spring scale (respectively) are :<br>

Question 31 : A rectangular iron block is placed over a table in different ways such that different faces touch the table. In all these cases, which of the following can be concluded?

Question 32 : Fill the blank.&#160;When a spherical body is allowed to fall through viscous medium its velocity increases, till the sum of viscous drag and upthrust is equal to ________.&#160;<br/>

Question 33 : How much would a W kg man weigh on the moon in terms of gravitational units?

Question 35 : How can you determine relative density of a substance using the Archimedes principle.<br/>

Question 36 : According to the law of floatation weight of floating body is -

Question 37 : Helium is preferred over hydrogen for filling balloons because it is&#160;

Question 39 : How much would a 60 kg boy weigh on the moon?<br/>Given: $g_{moon}=\dfrac {g_{earth}}{6}$<br/>

Question 40 : It is given thatA has higher relative density than B. Choose the correct option.

Question 41 : If W be the weight of the body and U be the upthrust force oft he liquid on the body then what happens if W=U<br>

Question 42 : The upward force exerted by the floating body on the fluid is known as upthrust.

Question 43 : A body floats in a liquid if the buoyant force is :

Question 44 : Weight on earth : _______ : : Weight on moon : 50 N

Question 46 : How does the buoyant force acting on the boat change if the boat is loaded so that more of the boat is below the water?<br>

Question 47 : <br>Specific gravity usually means relative density with respect to ice. Is the statement True or False

Question 48 : Two balls of masses in ratio $1 : 2$ are dropped from the same height. Find the ratio of the forces acting on them during motion.

Question 49 : When an object is immersed in water, it displaces $20\,kg$ of water. How much is the buoyant force acting on the object in Newtons?

Question 50 : If the gravitational force of earth suddenly disappears, then which of the following is correct?

Question 51 : A body weight $5 N$ in the air and $2 N$ when immersed in a liquid. The buoyant force is:<br/>

Question 52 : Assertion: A block floats in water with some part outside water. When whole system is given a constant upward acceleration then volume of block inside water remains unchanged in equilibrium Reason: Net force on block in both cases is zero.

Question 53 : The specific gravity of a solid with respect to a liquid is $\dfrac {4}{5}$ and specific gravity of a liquid with a respect to water is $\dfrac {10}{9}$, then specific gravity of solid with respect to water is:

Question 54 : A body weighs $700\ N$ on the surface of the earth. What is its weight on the surface of a planet whose mass is $1/7th$ of that of earth and radius is $1/2$ times that of earth?

Question 57 : The area of base of a cylinder vessel is $300 &#160;c{m}^{2}$. Water (density = $1000 &#160;kg &#160;{m}^{-3}$) is poured into it up to a depth of $6 &#160;cm$. &#160;($g=10 &#160;m &#160;{s}^{-2}$).Then find the pressure and thrust on the base.

Question 58 : A metal ball of density $7800 kg/m^{3}$ is suspected to have a large number of liner cavities. It weighs $9.8kg$ when weighed directly on a balance and $1.5kg$ less when immersed in water. The fraction by volume of the cavities in the metal bell is approrximately:

Question 59 : There is a planet name 'ALLEN' which has radius three times that of the earth and density two times that of the earth. The acceleration due to gravity on 'ALLEN' will be

Question 60 : 'Weight' of a body may have the following attributes.<br>I. It is the gravitational force acting on a body at the earth's surface<br>II. It is independent of the mass of the body<br>III. The body is weightless during free fall<br>IV. It is different at different places on earth's surface.<br>

Question 62 : Relative density of a body wrt a medium of density $\rho_1$ is a. What is the relative density of the body wrt a medium of density $\rho_2$

Question 63 : A point mass m is placed inside a spherical shell of radius R and mass M at a distance $R/2$ from the centre of the shell. The gravitational force exerted by the shell on the point mass is?

Question 64 : A body weighs $40\ g$ in air. If its volume is $10\ cc$, in water it will weight:

Question 65 : A block of wood is floating on water with its dimensions $50 &#160;cm\times 50 &#160;cm\times 50 &#160;cm$ inside water. The buoyant force acting on the block is X N. Find X. &#160;Take $g=9.8 \ N &#160; kg^{-1}$.&#160;

Question 66 : A man of weight mg is moving upwards in a rocket with acceleration $4$g. His apparent weight in side the rocket will be?

Question 67 : Inside a horizontally moving box, an experimenter finds that when an object is placed on a smooth horizontal table and is released, it moves with an acceleration of $10 m{ s }^{ -2 }$. In this box, if $1 kg$ body is suspended with a light string, the tension in the string in equilibrium position. (w.r.t. experimenter) will be (take $g=10 m{ s }^{ -2 }$)

Question 68 : If the acceleration due to gravity at the surface of the earth is $g$, the work done in slowly lifting a body of mass $m$ from the earth's surface to a height $R$ equal to the radius of the earth is

Question 69 : An object weights $72N$ on earth. Its weight at a height of $R/2$ from earth is:

Question 70 : For a given length of a pendulum, the time period is maximum<br>

Question 71 : When a body is weighed in a liquid, the loss in its weight depends upon:

Question 72 : A mass $M$ is lowered with the help of a string by a distance $x$ at a constant acceleration $g/2$. The work done by the string will be

Question 73 : A student is weighing an object using a spring balance.&#160;The weight and mass of the object are respectively ${(g= 10m/s^2)}$

Question 74 : A beaker containing water is placed on the platform of a spring balance. The balance reads $1.5\ kg$. A stone of mass $0.5\ kg$ and density ${10}^{4}\ kg/{m}^{3}$ is immersed in water without touching the walls of the beaker. What will be the balance reading now?

Question 75 : What is the acceleration of a body when it is projected vertically upwards?<br>

Question 77 : An object has a mass $m$ kg on earth. What will be its mass on the moon ?

Question 78 : 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 79 : The weight of a body on earth is $98 &#160;N$ where acceleration due to gravity is $9.8&#160; \ m &#160;{s}^{-2}$. What will be its weight on the moon where acceleration due to gravity is $1.6&#160; \ m &#160;{s}^{-2}$?

Question 80 : State whether true or false.<br/>The maximum heights reached by the bodies that are vertically projected with the same velocity on the surface of the moon and the earth are same.

Question 81 : A ball weighing 4 kg of density $4000 \; kg m^{-3}$ is completely immersed inwater of density $10^{3} \;kg m^{-3}$. Find the force of buoyancy on it in $N$. (Given $g = 10 \;m s^{-2}$)<br>

Question 82 : A spring balance measures the weight of an object in air to be $0.1 N$. It shows a reading of $0.08 N$ when the object is completely immersed in water. If the value of acceleration due to gravity is $10 {m}/{{s}^{2}}$, the volume of the object is

Question 83 : The weight of an object on earth is 800 N. If it were taken to the moon, it would weigh 100N. What is its mass on the moon? (Acceleration due to gravity on earth = 10 ms$^{-2}$)

Question 84 : A body&#160;of mass 50 kg has a volume of $\displaystyle 0.049{ m }^{ 3 }$, the buoyant force on it when immersed in water is:<br/>

Question 85 : A ball is thrown vertically upwards. The acceleration due to gravity:

Question 86 : Two planets of radii $r_1$ and $r_2$ are made from the same material.The ratio of the acceleration of gravity $\dfrac{g_1}{g_2}$at the surface of the two planets is-

Question 87 : A block of mass $5\ kg$ is at rest on a rough inclined surface. If angle of inclination of plane is ${60}^{o}$. then force applied by it on block is:

Question 88 : A force of 50N is applied on a nail of area&#160;0.001sq.cm. Then the thrust is:

Question 89 : <i></i>The specific gravity of ice is $0.9$. The area of the smallest slab of ice of height $0.5\ m$ floating in fresh water that will just support a $100\ kg$ man is

Question 90 : Earth is flattened at the poles and bulges at the equator. This is due to the fact that

Question 91 : When a piece of wood is suspended from the hook of a spring balance, it reads $70 &#160;gf$. The wood is now lowered into the water which results in floating the wood. What reading do you expect on the scale of spring balance?

Question 93 : Archimedes' principle states that when a body is totally or partially immersed in a fluid. the up thrust is equal to:

Question 94 : The radius of the moon is 1/4th the radius is $1.738 \times 10^8$ m. Calculate the mass of the earth. Calculate the value of g on the surface of the moon:

Question 95 : A string tied on a roof can bear a maximum tension of $50kg wt$. The minimum acceleration that can be acquired by a man of $98kg$ to descend will be (Take $g=9.8m/{s}^{2}$)

Question 96 : Two solids A and B float in water. It is observed that A floats with half of its volume immersed and Bfloatswith$2/3$of its volume immersed. The ratio of their densities is

Question 97 : State whether given statement is True or False<br/>As an object is moved deeper and deeper in a liquid, buoyant force on it increases gradually.<br/>

Question 98 : The relative density of an object is $0.3$. Will it float in water?

Question 99 : How much will a person with 72 N weight on Earth,weight on the moon?

Question 100 : A stone of density $2000$kg $m^{-3}$ completely immersed in a lake is allowed to sink from rest. If the effect of friction is neglected, then after $4$ seconds, the stone will reach a depth of:

Question 101 : If the distance between two bodies is increased by 25%, then the % change in the gravitationalforce is

Question 102 : A research satellite of mass 200 kg circles the earth in an orbit of average radius $\displaystyle \dfrac{3\mathrm{R}}{2},$ where R is the radius of&#160; the earth. Assuming the gravitational pull on a mass 1 kg on earth's surface to be 10 N, the pull on this satellite will be:<br/>

Question 103 : A man of mass m starts falling towards a planet of mass M and radius R. As he reaches near to the surface, height realizes that he will pass through a small hole in the planet. As he enters the hole, he seen that the planet is realize made of two pieces a spherical shell of negligible thickness of mass $\displaystyle\frac{2M}{3}$ and a point mass $\displaystyle\frac{M}{3}$ at the centre. Change in the force of gravity experienced by the man is?

Question 105 : The gravitational force between two bodies is decreased by $36$% when the distance between them is increased by $3m$. The initial distance between them is:

Question 106 : Two boxes of negligible mass are placed $2$ metres apart on the surface of planet $X$, initially $15$ identical steel ball bearings are placed in each box. Which statement is most accurate if $10$ of the ball bearings are transferred from box $1$ to box $2$?<br>

Question 108 : The density and acceleration due to gravity of the moon $3/5^{th} $ and $ 1/6 ^{th} $ those of the earth respectively. If the radius of the earth is $ 5.4 \times 10^6 m $ , how much is it for the moon :

Question 109 : Two bodies with masses $M_1$ and $M_2$ are initially at the rest and a distance $R$ apart. Then they move directly towards one another under the influence of their mutual gravitational attraction. What is the ratio of the distances traveled by $M_1$ to the distance traveled by $M_2$?

Question 110 : If R is the radius of a planet, g is the acceleration due to gravity then find the mean density of the planet

Question 111 : The relative density of a material is found by weighing the body first in air and then in water. If the weight in air is $(10.0 \pm 0.1)$ gf and the weight in water is $(5.0 \pm 0.1)$gf, then the maximum permissible percentage error in relative density is

Question 112 : A spherical planet, far out in space, has a mass $M_0$ and diameter $D_0$. A particle of mass $m$ falling freely near the surface of this planet will experience acceleration due to gravity which is equal to:

Question 113 : A mass of $M$ at rest is broken into two pieces having masses $m$ and $(M-m)$. The two masses are then separated by a distance. The gravitational force between them will be the maximum when the ratio of the masses [$m:(M-m)$] of the two parts is:

Question 115 : A body of weight $1N$ is placed at the surface of the earth, which is assumed to be a perfect sphere of radius $6400 km $ . It is taken to a height of $600 km $ , the weight of the body, in $N$ , would be :

Question 116 : Two spherical bodies of masses $m$ and $5\ M$ and radii $R$ and $2R$, respectively, are released in free space with initial separation between their centres equal to $12\ R$. If they attract each other due to gravitational force only, then the distance covered by the smaller body just before collision is<br>

Question 117 : A force of $\left( 7\hat { i } +6\hat { k } \right) $ newton makes a body move on a rough plane with a velocity of $\left( 3\hat { j } +4\hat { k } \right)\ m \ {s}^{-1} $. The power in watt is

Question 118 : A $60kg$ man is inside a lift which is moving up with an acceleration of $2.45\ {ms}^{-2}$. The apparent percentage change in his weight is:

Question 119 : An extremely small and dense neutron star of mass $M$ and radius $R$ is rotating at an angular frequency $\omega$. If an object is placed at its equator, it will remain stuck to it due to gravity if

Question 120 : 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 121 : Two astronauts have deserted their spaceship in a region of space far from the gravitational attraction of any other body. Each has a mass of $100kg$ and they are $100m$ apart. They are initially at rest relative to one another. how long will it be before the gravitational attraction brings them $1cm$ closer together?<br>

Question 122 : 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 123 : A box weights $196 N$ on a spring balance at the north pole. Its weight recorded on the same balance if it is shifted to the equator is close to (Take $g = 10 ms^{-2}$ at the north pole and the radius of the earth $= 6400 km$):

Question 124 : A boy carries a fish in one hand and a bucket (not full) of water in the other hand. If he places thefish in the bucket, the weight now carried by him (assume that water does not spill):

Question 125 : A planet has a miss of eight times the mass of earth and density is also equal to eight times the average density of the earth. If g be the acceleration due to earth's gravity on its surface, then acceleration due to gravity on planet's surface will be :

Question 126 : A ball with a weight of 20 N is thrown vertically upward . What is the acceleration of the ball just as it reaches the top of its path ?

Question 127 : When the radius of earth is reduced by 1% with out changing the mass, then the acceleration due to gravity will<br><br>

Question 128 : ACCELERATION DUE TO GRAVITY OF THE EARTH<br>Radius of earth is 6400 km and that of mars is 3200 km. Mass of mars is 0.1 that of earth's mass. Then the acceleration due to gravity on mars is nearly.

Question 129 : If the distance between the Sun and Earth is increased by three times then attraction between two will:

Question 130 : Assertion: A block of wood is floating in a pond of water and its apparent weigth is zero. Reason: The weight of water displaced (buoyant force) acting vertically upwards is just equal to the weight of the body which acts vertically downwards.

Question 131 : A body weighs $160\ N$ on the earth. Find its weight on another planet whose mass is $\dfrac {1}{4}th$ the mass of earth and radius $\dfrac {1}{3}rd$ that of the earth.

Question 132 : Find the value of $\theta $ such that the acceleration of $A$ is $ g/6 $ downward along the incline plane. (All surfaces are smooth)

Question 133 : Two spherical bodies of mass $M$ and $5M$ and radii $R$ and $2R$ respectively are released in free space with initial separation between their centres equal to $12 R$. If they attract each other due to gravitational force only, then the distance covered by the smaller body just before collision is

Question 134 : 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 135 : ball of mass 1 kg falls from a height of $5m$ above the free surface of water$.$ The relative density of the solid ball is s=$\frac{2}{3}.$ The ball travels a distance of 2 m under water and becomes stationary$.$ The work done by the resistive forces of water is

Question 136 : A body weighs $160\ N$ on the earth. Find its weight on another planet whose mass is $\dfrac {5}{2}$ times mass of earth and radius $\dfrac {4}{5}$ times that of earth.

Question 137 : Two bodies, each of mass M, are kept fixed with a separation $2$L. A particle of mass m is projected from the midpoint of the line joining their centres, perpendicular to the line. The gravitational constant is G. The correct statement(s) is (are).

Question 138 : The maximum vertical distance through which a fully dressed astronaut can jump on the earth is&#160;0.5 m. If mean density of the moon is two thirds&#160;that of the earth and radius is one quarter that of the earth, the maximum vertical distance through&#160;which he can jump on the moon and the ratio of&#160;time of duration of the jump on the moon to that&#160;on the earth are.

Question 139 : Two spherical bodies, having a mass of$M$ and $5 M$ and radius of$R$ and $2R$ respectively, arereleased in free space with initial separationbetween their centres equal to $12R$. If theyattract each other due to gravitational forceonly, then the distance covered by thesmaller body just before collision is<br>

Question 140 : 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 141 : A stone weight 100 N on the surface of the earth. The ratio of its weight at a height of half the radius of the earth to its weight at a depth of half the radius of the earth will be approximately

Question 142 : Two balls are dropped from the same height from places $A$ and $B$. The body at $B$ takes two seconds less to reach the ground at $B$ strikes the ground with a velocity greater than at $A$ by $10 m/s$. The product of the acceleration due to gravity at the two places $A$ and $B$ is:

Question 143 : A particle is dropped under gravity from rest from a height $h (g = 9.8 \,m/s^2)$ and it travels a distance $\dfrac{9h}{25}$ in the last second the height '$h$' is:

Question 144 : The moon's radius is $1/4$ times that of the earth and its mass $1/80$ times that of the earth. If g represents the acceleration due to gravity on the surface of the earth, then on the surface of the moon its value is :<br/>

Question 145 : 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

Question 146 : 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 147 : The angular velocity of the earth's rotation about its axis is $\omega$. An object weighed by a spring balance gives the same reading at the equator as at height $h$ above the poles, the value of $h$ will be:

Question 148 : Assume that the Earth goes round the sun in a circular orbit with a constant speed of $30 km/s$<br/>

Question 150 : If the mass of a planet is $10\%$ less than that of the earth and the radius is $20\%$ greater than that of the earth, the acceleration due to gravity on the planet will be.