Science - Gravitation and Pressure
Exam Duration: 45 Mins Total Questions : 30
Where will it be profitable to purchase one kilogram sugar?
- (a)
At the poles
- (b)
At the equator
- (c)
At 45° latitude
- (d)
At 40° latitude
The figure given below shows a planet in elliptical orbit around the sun S.
At what position will the kinetic energy of the planet be maximum?
- (a)
P1
- (b)
P4
- (c)
P3
- (d)
P2
If the mass of a body is M on the surface of the earth, what would be the mass of the same body on the surface of the moon?
- (a)
M/6
- (b)
Zero
- (c)
M
- (d)
2 M
Find the gravitational attraction between the two atoms in a hydrogen molecule when G is 6.67 X 10-11 Nm2 kg-2 mass of a hydrogen atom is 1.67 x 10-27 kg and distance between the two atoms is 1 A.
- (a)
11.14 x 10-18 N
- (b)
2.39 x 10-45 N
- (c)
1.86 X 10-44 N
- (d)
4.18 x 10-23 N
The distances of two planets (Neptune and Saturn) from the sun are 1013 m and 1012 m respectively. Find the ratio of the time periods of the planets.
- (a)
\(100:1\)
- (b)
\(1:\sqrt { 10 } \)
- (c)
\(\sqrt { 10 } :1\)
- (d)
\(10\sqrt { 10 } :1\)
Two spheres each of mass 105 kg and radius 10m are kept in contact. Find the force of gravitation acting between them.
- (a)
10-3 N
- (b)
6.67 x 10-3N
- (c)
6.67 x 10-11 N
- (d)
10-11 N
A body weighs 700 N on the surface of the earth. What is its weight on the surface of a planet, whose mass is 1/7 th and radius is 1/2 as that of the earth?
- (a)
400 N
- (b)
300 N
- (c)
700 N
- (d)
500 N
A stone is thrown upwards with a speed 'u' from the top of a tower. It reaches the ground with a velocity '3u'. Find the height of the tower.
- (a)
\(\sqrt { 3 } \)
- (b)
\(\frac { { 2 }u^{ 2 } }{ g } \)
- (c)
\(\frac { { 3u }^{ 2 } }{ g } \)
- (d)
\(\frac { { 4u }^{ 2 } }{ g } \)
Points P,Oand Rare in a vertical line such that PO= OR. A ball at the top-most point 'P'is allowed to fall freely. What is the ratio of the times of descent through PO and PR?
- (a)
\(\frac { 3 }{ 2 } \)
- (b)
\(\frac { 3 }{ \sqrt { 2 } +1 } \)
- (c)
\(\frac { 1 }{ \sqrt { 2 } -1 } \)
- (d)
\(\frac { 5 }{ 2 } \)
A wooden block of mass 10 g is dropped on the top of a cliff 100 m high. Simultaneously, a bullet of mass 10 g is fired from the foot of the cliff upward with a velocity of 100 m s -1. At what time will the bullet and the wooden block meet? (9 = 9.8 m s-2)
- (a)
1 s
- (b)
2 s
- (c)
3 s
- (d)
4 s
A body falling freely from rest covers \(\frac { 7 }{ 16 } \) of the total height in the last second of its fall. What is the height from which it falls?
- (a)
24.2 m
- (b)
38.4 m
- (c)
78.4 m
- (d)
46.8 m
If a freely falling body travels in the last second a distance equal to the distance travelled by it in the first 3 seconds. Find the time of its travel
- (a)
3 s
- (b)
4 s
- (c)
5 s
- (d)
6 s
Two stones are thrown from the top of a building with the same speed u, one in the upward direction and the other in the downward direction. When they reach the ground, they acquire certain velocities v1 and v2 respectively. What is the ratio of v1 and v2?
- (a)
1:1
- (b)
1:2
- (c)
2:1
- (d)
2:3
A freely falling body covers half of its journey from the top of a tower in 0.5 s. What is the height of the tower?
- (a)
4.9 m
- (b)
2.45 m
- (c)
9.8 m
- (d)
9m
A stone is dropped from a tower. It was found that it covered a distance of 45 m during its last second of the fall. Calculate the time of the fall and the height of the tower? (9 = 70 m S-2)
- (a)
5 s,45 m
- (b)
10 s,90 m
- (c)
5 s, 125 m
- (d)
10 s, 100 m
A liquid exerts a pressure of 100,999 Pa on an object when it is 73.5 cm below the liquid surface. What is the density of the liquid? (Take 9 = 70 m S-2)
- (a)
136 kg m-3
- (b)
272 kg m-3
- (c)
13,700 kg m-3
- (d)
27,200 kg m-3
The diagram given below shows a special flask filled with water
Which of the followi ng statements is true?
- (a)
Point P has a higher pressure than point Q
- (b)
Point R has a higher pressure than point Q
- (c)
Point Q has the highest pressure as compared to point P and point R
- (d)
Point P,point Q and point R have the same pressure
A rectangular tank of 6 m long,2 m broad and 2 m deep is full of water, what is the thrust acting on the bottom of the tank?
- (a)
23.52 x 104 N
- (b)
23.52 N
- (c)
11.76 x 104
- (d)
3.92 X 104 N
When a body is immersed in a liquid, what is the loss in its weight equal to?
- (a)
The weight of the liquid
- (b)
The weight of the body
- (c)
The difference in the weights of body in air and in liquid
- (d)
The upthrust of liquid on the body
When a body is immersed in a liquid, the loss in its weight is equal to the upthrust of liquid on the body
- (a)
Its true weight is V σ g
- (b)
Loss in its weight is V σ g
- (c)
Its apparent weight is zero.
- (d)
Its density p is greater than that of liquid σ
Which of the following is NOT a factor on which pressure at a point inside a liquid depends?
- (a)
The depth of the point below the surface of the liquid
- (b)
The nature of the liquid
- (c)
The acceleration due to gravity at that point
- (d)
The shape of the containing vessel
Two stretched membranes of area 2 cm2 and3 cm2 are placed in a liquid at the same depth. Find the ratio of the pressure on them.
- (a)
1: 1
- (b)
2: 3
- (c)
3: 2
- (d)
22:32
If a body floats with \(\left( \frac { p }{ q } \right) ^{ th }\) of its volume above the surface of water, find the relative density of the body.
- (a)
\(\frac { q+p }{ q } \)
- (b)
\(1-\frac { p }{ q } \)
- (c)
\(\frac { 1-p }{ q } \)
- (d)
\(\frac { p }{ q } \)
A rectangular iron block is placed over a table in differents ways such that different faces touch the table. In all these cases, which of the following can be concluded?
- (a)
The block exerts the same thrust and same pressures.
- (b)
The block exerts the same thrust and different pressure
- (c)
The block exerts different thrusts but the same pressures.
- (d)
The block exerts different thrusts and different pressures
A stone is thrown vertically upwards with an initial velocity of 14m S-1. Find the time taken by the stone to strike the ground. (Take g=9.8 m S-2)
- (a)
2.86 s
- (b)
3.46 s
- (c)
3.86 s
- (d)
4.86 s
Choose the correct statement among the following
- (a)
The upper surface of a stationary liquid is always horizontal.
- (b)
The pressure of a given liquid is directly proportional to the depth of the liquid.
- (c)
Pressure at a given depth inside a stationary liquid is different at all points on the horizontal plane
- (d)
Both (A) and (B)
If suddenly the gravitational force of attraction between the earth and a satellite revolving around it becomes zero, what will happen?
- (a)
The satellite will continue to move in its orbit with the same velocity.
- (b)
The satellite will move tangentially and escape away from its orbit.
- (c)
The satellite will become stationary in its orbit.
- (d)
The satellite will move towards the earth
Which of the following statements regarding gravitational force existing between two bodies is true?
- (a)
The first body exerts attractive force on the second body while the second body exerts repulsive force on the first body.
- (b)
The gravitational force is zero when they are kept in vacuum.
- (c)
Force exerted by the first body on the second is not equal to the force exerted by the second body on the first.
- (d)
Force exerted by the first body on the second body is equal to the force exerted by the second body on the first.
A wooden cylinder floats vertically in water with one fourth of its length immersed. What will be the density of wood?
- (a)
It equals to the density of water.
- (b)
It equals to half the density of water.
- (c)
It equals to one fourth the density of water.
- (d)
It equals to three fourths the density of water
A stone is dropped from a building and 2 seconds later another stone is dropped. How far apart are these two stones by the time the first one reaches a speed of 30 m s-1 (Take 9 = 10 m S-2)
- (a)
80 m
- (b)
100 m
- (c)
60 m
- (d)
40 m