Gravitation Test

Result

Gravitation Test - 20

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

Calculate the weight of a body of mass $$10 kg$$.

A
$$10$$ $$kgf$$

B
$$98$$ N

C
98 kg

D
Both A & B

Solution

$$ F= mg =$$ weight of the body
$$ \Rightarrow Weight = 10 \times 9.8 = 98 N$$
Now, weight in $$kgf = W/g = 98/9.8 = 10 kgf$$
Question 2
1 / -0

Which of the following is/are true about the value of g

A
The value of g is minimum at equator

B
The value of g is maximum at poles

C
Average value of g is 9.8 $$ ms^{-2}$$

D
All the above

Solution

At a given place, the value of acceleration due to gravity is constant but it varies from one place to another place on the earth surface. It is due to this fact that earth is not a perfect sphere. It is flattened at the poles and bulges out at the equator.

At equator effect of centrifugal force is maximum so g is minimum.
At poles effect of centrifugal force is minimum so g is maximum.
And the average value of g is $$9.8m/s^2$$
Question 3
1 / -0

What will be the weight of a body of mass $$m$$ kg at the centre of the earth?

A
$$mg$$ newton

B
$$m/g$$ newton

C
$$m$$ newton

D
$$0$$ newton

Solution

We know that $$Weight = mass \times g $$
Now, $$g=0$$ at the centre of the earth.
So, weight of the body at the centre of the earth $$=m \times 0=0\ N$$
Question 4
1 / -0

Write the approximate weight of a body of mass $$5 kg$$ ?

A
$$50$$ $$N$$

B
$$5$$ $$N$$

C
$$0.5$$ $$N$$

D
$$50000$$ $$N$$

Solution

$$ F= mg =$$ Weight of body
here, we consider $$g = 10 m/s^{2}$$
So, weight $$=5 \times 10 = 50\ N$$
Question 5
1 / -0

What is the S.I unit of upthrust ?

A
$$Pa$$

B
$$N$$

C
$$kg$$

D
$$kg m^2$$

Solution

Upthrust is nothing but buoyant force. When a rigid object is submerged in a fluid (completely or partially), there exits an upward force on the object that is equal to the weight of the fluid that is displaced by the object.
And therefore, Its unit is equal to that of force(since buoyant force is a kind of force), which is $$N$$.
Question 6
1 / -0

With increase in surface area,

A
pressure increases

B
pressure decreases

C
pressure remains unchanged

D
pressure becomes zero

Solution

If there are two wooden plank with different surface area and same thrust F is applied on them in vertically downward direction. Then, pressure will be less on surface for the plank having more surface area.
Question 7
1 / -0

Relative density of silver is $$10.8$$. Its density in $$g/cm^3$$ is

A
$$10.8$$

B
$$5.6$$

C
$$10$$

D
$$13.8$$

Solution

$$ R.D = \dfrac{\text{Density of object}}{\text{Density of water}}$$
Here, Density of water $$= 1g/cm^{3}$$
So, $$R.D = \dfrac{\text{Density of silver}}{\text{Density of water}}$$
$$\text{Density of silver} = R.D \times \text{Density of water }= 10.8$$ x$$ 1 = 10.8 g/cm^{3}$$
Question 8
1 / -0

State the universal law of gravitation.

A
Everybody in this universe attracts every other body with a force, which is directly proportional to the product of their masses and inversely proportional to the square of distance between their centers.

B
No body in this universe attracts other body with a force, which is directly proportional to the product of their masses and inversely proportional to the square of distance between their centers.

C
Everybody in this universe attracts every other body with a force, which is directly proportional to the product of their masses and inversely proportional to the cube of distance between their centers.

D
Everybody in this universe attracts every other body with a force, which is directly proportional to the product of their masses and inversely proportional to the square of distance between their surfaces.

Solution

$$\bullet\textbf{Explanation}$$
Newton in 1687 put forward a law which stated that any particle of matter in the universe attracts any other particle with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between the particles.
$$\bullet\textbf{Mathematical Explanation}$$
If $$F$$ is the force of attraction between two particle, then

$$F \propto m_1m_2$$

$$F \propto \dfrac 1{r^2}$$

=> $$F \propto \dfrac{m_1m_2}{r^2}$$

$$F = \dfrac{Gm_1m_2}{r^2}$$

where, $$m_1$$ and $$m_2$$ are the masses
$$r$$ is the distance between them and
$$G$$ is the gravitational constant

The value of $$G = 6.673 \times 10^{-11}\;N\;m^2/kg^2$$

Thus, option A is correct.
Question 9
1 / -0

Which among the following is not a property of mass?

A
It is the amount of matter contained in a body.

B
It is measured by a physical balance.

C
It varies as per the location.

D
Its S.I unit is kilogram.

Solution

1) Mass:
(a) It is the amount of matter contained in a body.
(b)It is measured by a physical balance.
(c) It is constant at all the places in the universe.
(d) Its S.I unit is kilogram.

(2) Weight:
(a) It is the force of gravity acting on a body.
(b) It is measured by a spring balance.
(c)It is variable and changes with the change in acceleration due to gravity.
(d) Its S.I unit is Newton.
Question 10
1 / -0

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:

A
Free fall

B
Accelerated fall

C
Projectile motion

D
Constant velocity

Solution

When an object moves with a constant acceleration under the only effect of acceleration due to gravity at that place, the motion is called free fall.

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Gravitation Test - 20

Result

Gravitation Test - 20

Score

-

Rank

-

SHARING IS CARING

Question 1

$$10$$ $$kgf$$

$$98$$ N

98 kg

Both A & B

Solution

Question 2

The value of g is minimum at equator

The value of g is maximum at poles

Average value of g is 9.8 $$ ms^{-2}$$

All the above

Solution

Question 3

$$mg$$ newton

$$m/g$$ newton

$$m$$ newton

$$0$$ newton

Solution

Question 4

$$50$$ $$N$$

$$5$$ $$N$$

$$0.5$$ $$N$$

$$50000$$ $$N$$

Solution

Question 5

$$Pa$$

$$N$$

$$kg$$

$$kg m^2$$

Solution

Question 6

pressure increases

pressure decreases

pressure remains unchanged

pressure becomes zero

Solution

Question 7

$$10.8$$

$$5.6$$

$$10$$

$$13.8$$

Solution

Question 8

Everybody in this universe attracts every other body with a force, which is directly proportional to the product of their masses and inversely proportional to the square of distance between their centers.

No body in this universe attracts other body with a force, which is directly proportional to the product of their masses and inversely proportional to the square of distance between their centers.

Everybody in this universe attracts every other body with a force, which is directly proportional to the product of their masses and inversely proportional to the cube of distance between their centers.

Everybody in this universe attracts every other body with a force, which is directly proportional to the product of their masses and inversely proportional to the square of distance between their surfaces.

Solution

Question 9

It is the amount of matter contained in a body.

It is measured by a physical balance.

It varies as per the location.

Its S.I unit is kilogram.

Solution

Question 10

Free fall

Accelerated fall

Projectile motion

Constant velocity

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.