Gravitation Test

Result

Gravitation Test - 42

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

Relation between buoyant force and the volume of an object immersed in liquid is:
Given,
$$\rho_{liq}$$ = Density of liquid
$$\rho_{obj}$$ = Density of object
$$V_{total}$$ = Total volume of object
$$V_{sub}$$ = Submerged volume of the object

A
$$F_{B} = \rho_{liq} V_{sub}g$$

B
$$F_{B} = \rho_{obj} V_{sub}g$$

C
$$F_{B} = \rho_{liq} V_{total}g$$

D
$$F_{B} = \rho_{obj} V_{total}g$$

Solution

The upward force applied by the fluid on the object when it is submerged in a fluid is known as the Buoyant force. According to the Archimedes' principle, the upward buoyant force is equal to the weight of the fluid that the body displaces .

Hence, $$F_B = \rho_{liq}V_{sub}g$$
Question 2
1 / -0

What is the relationship between buoyant force and the weight of liquid displaced?

A
Buoyant force is greater

B
Buoyant force is lesser

C
Buoyant force is equal to weight of liquid displaced

D
None of the above

Solution

When a body is partly or completely immersed in water (or any other liquid), then according to archimedes principle.
Loss in weight of body = Weight of water (liquid) displaced by the body = Buoyant force or upthrust exerted by water (any liquid) on the body.
Hence, the relationship between buoyant force and the weight of liquid displaced is that they are equal.
Question 3
1 / -0

If relative density of a substance in $$0.8$$, is it heavier or lighter than water?

A
Lighter

B
Heavier

C
Of equal weight

D
None of these

Solution

The relative density of a substance is a characteristic property of the substance that remains the same under specific conditions. The relative density of water is 1. If a substance has a relative density that is greater than 1, it will sink in water and if its relative density is less than 1, it will float in water.
In this case, the relative density of a substance is 0.8. Hence, the substance float in water.
Question 4
1 / -0

Directions For Questions

The diagram shows an iceberg. Answer the questions relating to it.

...view full instructions

How much of the iceberg has a weight equal to the buoyant force?

A
All of it

B
The section from A to B.

C
The section from B to C.

D
Can't be determined

Solution

According to Archimedes principle an object immersed in a liquid experience an upward force called buoyant force ,which is equal to the weight of fluid displaced.
And if this upward force is equal to weight of object then object keep floating , it do not sink because weight has been cancelled by buoyant force.
Since the iceberg is shown as floating it means all of it's weight has been canceled by the buoyant force.
So weight of whole iceberg is equal to buoyant force.
Question 5
1 / -0

An apple falls from a tree because of gravitation between the earth and apple. If $$F_1$$ is the magnitude of force exerted by the earth on the apple and $$F_2$$ is the magnitude of force exerted by apple on earth, then

A
$$F_1$$ is very much greater than $$F_2$$

B
$$F_2$$ is very much greater than $$F_1$$

C
$$F_1$$ is only a little greater than $$F_2$$

D
$$F_1$$ and $$F_2$$ are equal

Solution

From Newton’s third law of motion: Every action has equal and opposite reaction. Thus, F1 =F2 where, F1 is the magnitude of force exerted by the earth on the apple and F2 is the magnitude of force exerted by apple on earth.
Question 6
1 / -0

A planet whose mass and radius are both half of that of earth. Acceleration due to gravity(g) at its surface should be:

A
$$29.4 m/sec^2$$

B
$$19.6 m/sec^2$$

C
$$9.8 m/sec^2$$

D
$$4.9 m/sec^2$$

Solution

Acceleration due to gravity on earth,$$g=\dfrac{GM}{R^2}$$
Acceleration due to gravity on planet,$$g'=\dfrac{G(\dfrac{M}{2})}{(\dfrac{R}{2})^2}=2\dfrac{GM}{R^2}=2g=19.6m/sec^2$$
Question 7
1 / -0

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

A
$$3:4$$

B
$$4:3$$

C
$$\sqrt{3}:2$$

D
$$9:16$$

Solution

Answer is D.

The thrust acting on the cirular disc is dependent on the area covered by the circular disc and the density of the fluid.
In this case, the radii of the two circular discs are given as 3 cm and 4 cm and density of the liquid remains the same.
The area covered is given by $$\pi { r }^{ 2 }$$.
So, the ratio of their thrust will be given as: $${ 3 }^{ 2 }:{ 4 }^{ 2 }= 9:16$$
Question 8
1 / -0

Pick up the correct relationship

A
$$G=Fd^{2}/M\times m$$

B
$$G=g\:M/R^{2}$$

C
$$G=g$$

D
$$g=G\:d/M$$

Solution

Gravitational force between two masses is given by
$$F=\dfrac{GMm}{d^2}$$
Where $$M$$ $$m$$ are both masses respectively and $$d$$ is the distance between them.
Thus,$$G= \dfrac{Fd^2}{Mm}$$
Question 9
1 / -0

Which of the following statements about weight is/are false ?
$$1$$. Weight does not change when location changes.
$$2$$. Weight is a force.
$$3$$. Weight is measured in kilograms.
$$4$$. Weight is proportional to the amount of gravity acting on an object.

A
$$1$$ only

B
$$1\;and\;3$$ only

C
$$2\;and\;4$$ only

D
$$1,\,3\;and\;4$$ only.
Solution
Answer is B.
Only the mass of an object doesn't change when an object's location changes. Weight, on the other hand does change with location as it the measurement of the pull of gravity on an object.
The unit of measurement for weight is that of force, which in the International System of Units (S.I.) is the newton.

Hence, the statements 1 and 3 are false.
Question 10
1 / -0

Any solid will not sink in water if its relative density is

A
Less than 1

B
Equal to 1

C
Greater than 1

D
Infinite

Solution

If the reference material is water, then a substance with a relative density (or specific gravity) less than $$1$$ will float in water. For example, an ice cube, with a relative density of about $$0.91$$, will float. A substance with a relative density greater than $$1$$ will sink.
$$\text{specific gravity} = \dfrac{\text{density of the substance}}{\text{density of the water}}$$

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Gravitation Test - 42

Result

Gravitation Test - 42

Score

-

Rank

-

SHARING IS CARING

Question 1

$$F_{B} = \rho_{liq} V_{sub}g$$

$$F_{B} = \rho_{obj} V_{sub}g$$

$$F_{B} = \rho_{liq} V_{total}g$$

$$F_{B} = \rho_{obj} V_{total}g$$

Solution

Question 2

Buoyant force is greater

Buoyant force is lesser

Buoyant force is equal to weight of liquid displaced

None of the above

Solution

Question 3

Lighter

Heavier

Of equal weight

None of these

Solution

Question 4

All of it

The section from A to B.

The section from B to C.

Can't be determined

Solution

Question 5

$$F_1$$ is very much greater than $$F_2$$

$$F_2$$ is very much greater than $$F_1$$

$$F_1$$ is only a little greater than $$F_2$$

$$F_1$$ and $$F_2$$ are equal

Solution

Question 6

$$29.4 m/sec^2$$

$$19.6 m/sec^2$$

$$9.8 m/sec^2$$

$$4.9 m/sec^2$$

Solution

Question 7

$$3:4$$

$$4:3$$

$$\sqrt{3}:2$$

$$9:16$$

Solution

Question 8

$$G=Fd^{2}/M\times m$$

$$G=g\:M/R^{2}$$

$$G=g$$

$$g=G\:d/M$$

Solution

Question 9

$$1$$ only

$$1\;and\;3$$ only

$$2\;and\;4$$ only

$$1,\,3\;and\;4$$ only.

Solution

Question 10

Less than 1

Equal to 1

Greater than 1

Infinite

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.