Advertisements
Advertisements
प्रश्न
The gravitational field in a region is given by \[E = \left( 2 \overrightarrow{i} + 3 \overrightarrow{j} \right) N {kg}^{- 1}\] . Show that no work is done by the gravitational field when a particle is moved on the line 3y + 2x = 5.
[Hint : If a line y = mx + c makes angle θ with the X-axis, m = tan θ.]
Advertisements
उत्तर
The gravitational field in a region is given by \[\overrightarrow{E} = 2 \hat i + 3 \hat j\]
Slope of the electric field, \[m_1 = \tan \theta_1 = \frac{3}{2}\]
The given line is 3y + 2x = 5.
Slope of the line, \[m_2 = \tan \theta_2 = - \frac{2}{3}\]
We can see that m1m2 = −1
Since the directions of the field and the displacement are perpendicular to earth other, no work is done by the gravitational field when a particle is moved on the given line.
APPEARS IN
संबंधित प्रश्न
The earth and the moon are attracted to each other by gravitational force. Does the earth attract the moon with a force that is greater or smaller or the same as the force with which the moon attracts the earth? Why?
If the moon attracts the earth, why does the earth not move towards the moon?
What is the importance of the universal law of gravitation?
If you compare the gravitational force on the Earth due to the Sun to that due to the Moon, you would find that the Sun’s pull is greater than the Moon’s pull. (You can check this yourself using the data available in the succeeding exercises). However, the tidal effect of the Moon’s pull is greater than the tidal effect of Sun. Why?
Choose the correct alternative:
Acceleration due to gravity increases/decreases with increasing altitude.
Choose the correct alternative:
Acceleration due to gravity is independent of mass of the earth/mass of the body.
Universal law of gravitation states that every object exerts a gravitational force of attraction on every other object. If this is true, why don’t we notice such forces ? Why don’t the two objects in a room move towards each other due to this force ?
A ball is thrown vertically upwards. It goes to a height 20 m and then returns to the ground. Taking acceleration due to gravity g to be 10 ms-2 , find :
the total time of journey of the ball .
All objects in the universe attract each other along the line joining their________.
A ball is thrown up with a speed of 4.9 ms-1.
Calculate the maximum height it would gain before it begins to fall.
A ball is thrown up with a speed of 4.9 ms-1.
Prove that the time of ascent is equal to the time of descent.
Where will you weigh more: at the centre of the earth or at the surface of the earth?
What does a force do in the following case?
You apply brakes to a running car.
Name and state the action and reaction in the following case:
A person walking on the ground.
Why does a ball moving on a table top eventually stops?
What is the difference between gravity and gravitation?
The distance-time values for an object moving along straight line are given below:
| Time (s) | Distance (m) |
| 0 | 0 |
| 1 | 1 |
| 2 | 8 |
| 3 | 27 |
The gravitational force between two bodies is directly proportional to the product of the masses of those bodies and is _______ of the distance between them.
State the universal law of gravitation and derive its mathematical expression.
Write the answer of the question with reference to laws of gravitation.
Write the value of the universal gravitational constant.
