Gravitation Test

Result

Gravitation Test - 54

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

If the density of a liquid increases, the upthrust will ____

A
Increase

B
Decrease

C
Increase or decrease

D
Remain the same

Solution

Upthrust by a liquid on an object is calculated as -
$$\text{Upthrust} = \text{Volume of the object}\times \text{density of the liquid}\times \text{gravitational acceleration}$$
Therefore, if the density of the liquid increases then the upthrust also increases.
Question 2
1 / -0

Every liquid exerts an upward force on the objects immersed in it. The upward force is called ________.

A
Gravitational force

B
Buoyant force

C
Muscular force

D
Magnetic force

Solution

The buoyant force is the upward force exerted by the liquid on an object immersed in it.
and it is given as
Buoyant force = (Volume of body immersed) $$\times $$ (density of liquid) $$\times $$ (acceleration due to gravity)
Question 3
1 / -0

The mass of a planet is double and its radius is half compared to that of earth. Assuming $$g=10m/s^2$$ on earth, the acceleration due to gravity at the planet will be :

A
$$10m/s^2$$

B
$$20m/s^2$$

C
$$40m/s^2$$

D
None of these

Solution

Using the relation, $$g=\displaystyle\frac{GM}{R^2}$$
Aceleration due to gravity at earth , $$g_e=\displaystyle\frac{GM_e}{R_e^2}$$...........(1)
Aceleration due to gravity at planet , $$g_p=\displaystyle\frac{GM_p}{R_p^2}$$ ............(2)
Given that $$ M_p= 2M_e $$, $$R_p = \dfrac{1}{2}R_e$$ , $$g_e= 10 m/s^2$$
Dividing (2) by (1) we get,
$$\displaystyle\frac{g_p}{g_e}=\frac{M_p}{M_e}\times \frac{R^2_e}{R^2_p}=2\times (2)^2$$
$$g_p=8g_e$$
$$\therefore g_p=8\times 10=80m/s^2$$.
Thus option D is correct.
Question 4
1 / -0

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

A
$$20 {cm}^{3}$$

B
$$80 {cm}^{3}$$

C
$$200 {cm}^{3}$$

D
$$2 {cm}^{3}$$

Solution

Given,
Weight of the object in air $$=0.1N$$
Weight of the object in water $$=0.08N$$
The volume of the object $$(V)=?$$

The reduction in weight is due to buoyant force $$(F_B)$$.
$$\therefore$$ Buoyant force $$(0.1-0.08)= 0.02 N$$
From Archemede's principle,
$$F_B = \text{Weight of the displaced water}$$ $$= \text{ Volume of water displaced} \times \text{ Density of water} \times g $$
$$\Rightarrow 0.02= V \times { 10 }^{ 3 }\times 10$$
$$\Rightarrow V = \dfrac { 0.02 }{ { 10 }^{ 4 } } { m }^{ 3 }=0.02\times \dfrac { { 10 }^{ 6 } }{ { 10 }^{ 4 } } { cm }^{ 3 }=2{ cm }^{ 3 }$$
Question 5
1 / -0

Which of the following equations represent Newton's law of gravitation?

A
$$F= \cfrac {G{m}_{1}{m}_{2} }{ {d}} $$

B
$$F= \cfrac {G{m}_{1}{m}_{2} }{ {d}^{2} } $$

C
$$F= \cfrac {G{m}_{1} }{ {d}^{2} } $$

D
$$F= \cfrac {{m}_{1}{m}_{2} }{ {d}^{2} } $$

Solution

Newton's law of gravitation states that:
Every object in the universe attracts every other object with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
Thus, the equation representing this law is:
$$F= \cfrac {G{m}_{1}{m}_{2} }{ {d}^{2} } $$
Question 6
1 / -0

Acceleration due to gravity on moon is $$0.166$$ times than that on the earth. A man weighing $$60$$kg on earth would weigh __________kg on moon.

A
$$60$$kg

B
$$30$$kg

C
$$16.6$$kg

D
$$10$$kg

Solution

Weight of moon $$=\dfrac { 1 }{ 6 } $$ weight of earth
Given weight at earth $$=60kg$$
$$=\dfrac { 1 }{ 6 } \times 60kg=10kg$$
Question 7
1 / -0

'G' represents
I. Acceleration due to gravity.
II. Weight
III. Gravitational constant
Which combination is correct?

A
II and III only

B
I and III only

C
III only

D
I, II and III

Solution

$$G$$ denotes gravitational constant where as $$g$$ denotes acceleration due to gravity and weight is given by $$W=mg$$
Question 8
1 / -0

High tides at antipodes are caused due to.

A
Centrifugal, centripetal and gravitational pull of the sun

B
Gravitational pull of the sun

C
Gravitational pull of the moon and the sun

D
Centrifugal, centripetal and gravitational pull of the sun and the moon

Solution

High tides at antipodes are caused due to gravitational pull of moon and sun. A particularly high tide (Spring tide) occurs when these two bodies are in line and both pull in the same direction.
Question 9
1 / -0

On doubling the distance between two masses the gravitational force between them will:

A
Remain unchanged

B
Become one-fourth

C
Become half

D
Become double

Solution

Consider two objects of masses $$m_1$$ and $$m_2$$, separated by a distance $$r$$.
According to Newton's law of gravitation,

$$F=G\dfrac{m_1m_2}{r^2}$$ (where, $$G=$$ Gravitational constant)
If distance between the two masses doubles

$$r'=2r$$
Then,

$$F'=G\dfrac{m_1m_2}{r'^2}$$

$$F'=G\dfrac{m_1m_2}{(2r)^2}$$

$$F'=G\dfrac{m_1m_2}{4r^2}$$

$$F'=\dfrac{F}{4}$$

On doubling the distance between two masses the gravitational force between them will become one-fourth.
Question 10
1 / -0

A body dropped from a certain height attains the same velocity as another falling with an initial velocity u from a height h below the first body. Which one of the following gives the correct expression for the square of the initial velocity of the second body $$(u)$$? (g is the acceleration due to gravity).

A
$$2$$gh

B
$$4$$gh

C
gh

D
$$8$$gh

Solution

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Gravitation Test - 54

Result

Gravitation Test - 54

Score

-

Rank

-

SHARING IS CARING

Question 1

Increase

Decrease

Increase or decrease

Remain the same

Solution

Question 2

Gravitational force

Buoyant force

Muscular force

Magnetic force

Solution

Question 3

$$10m/s^2$$

$$20m/s^2$$

$$40m/s^2$$

None of these

Solution

Question 4

$$20 {cm}^{3}$$

$$80 {cm}^{3}$$

$$200 {cm}^{3}$$

$$2 {cm}^{3}$$

Solution

Question 5

$$F= \cfrac {G{m}_{1}{m}_{2} }{ {d}} $$

$$F= \cfrac {G{m}_{1}{m}_{2} }{ {d}^{2} } $$

$$F= \cfrac {G{m}_{1} }{ {d}^{2} } $$

$$F= \cfrac {{m}_{1}{m}_{2} }{ {d}^{2} } $$

Solution

Question 6

$$60$$kg

$$30$$kg

$$16.6$$kg

$$10$$kg

Solution

Question 7

II and III only

I and III only

III only

I, II and III

Solution

Question 8

Centrifugal, centripetal and gravitational pull of the sun

Gravitational pull of the sun

Gravitational pull of the moon and the sun

Centrifugal, centripetal and gravitational pull of the sun and the moon

Solution

Question 9

Remain unchanged

Become one-fourth

Become half

Become double

Solution

Question 10

$$2$$gh

$$4$$gh

gh

$$8$$gh

Solution

User

Question Analysis

My Perfomance

Score

-

Rank

-

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.