Ten , one rupees coin are put on the top at of each other on a table. Each coin has a mass 'm'. Give the magnitude and direction of - (1)- The force of 7th coin (counted from bottom) due to all coins on its top. (2)- The force of 7th coin by 8th coin. (3)- The reaction of 6th coin on the 7th.

To find the magnitude and direction of the forces in the given scenario, we can consider the following:

1) The force of the 7th coin due to all coins on top:
To find the force exerted on the 7th coin by the coins above it, we need to sum up the gravitational forces from each of those coins.
Since each coin has the same mass 'm' and the gravitational force is directly proportional to mass, the force of each coin on the 7th is also 'm' times the acceleration due to gravity 'g'.

The magnitude of the force is given by:
Magnitude = (mass of 7th coin) × (acceleration due to gravity) = m × g

The direction of the force will be downward since it is the force of gravity acting on the 7th coin.

2) The force of the 7th coin by the 8th coin:
The force between the 7th and 8th coin can be found using Newton's third law of motion, which states that every action has an equal and opposite reaction.
Since the 8th coin exerts a force on the 7th coin, the force exerted by the 7th coin on the 8th will have the same magnitude but the opposite direction.

The magnitude of the force is the same as calculated in question 1:
Magnitude = m × g

The direction of the force will be upward since it is the reaction force in response to the downward force of gravity.

3) The reaction of the 6th coin on the 7th:
Similar to the previous case, the force exerted by the 6th coin on the 7th will have the same magnitude but the opposite direction to the force the 7th coin exerts on the 6th.

The magnitude of the force is again m × g.

The direction of the force will be upward as it is the reaction force from the downward force exerted by the 7th coin.

Thus, the answers are:
1) Magnitude: m × g
Direction: Downward
2) Magnitude: m × g
Direction: Upward
3) Magnitude: m × g
Direction: Upward

To find the magnitude and direction of the forces in this scenario, you need to consider the force of gravity acting on each coin and the principles of Newton's third law. Let's break down each question:

(1) The force on the 7th coin due to all the coins on top of it:
To calculate this force, you need to consider that each coin is supporting the weight of the coins above it. The force on each coin is the product of its mass and acceleration due to gravity (9.8 m/s²).

For the 7th coin, there would be 3 coins above it (since we start counting from the bottom up). So the total force acting on the 7th coin due to the other coins can be calculated by summing the weights of the 4 coins above it.

Magnitude: The magnitude of the force on the 7th coin would be 4 times the weight of a single coin.
Direction: The direction would be downwards, towards the table.

(2) The force on the 7th coin by the 8th coin:
Since the 8th coin is just above the 7th coin, it will exert a force on the 7th coin due to gravitational attraction. The magnitude of the force is the weight of the 8th coin, which is m × 9.8 m/s².

Magnitude: The magnitude of the force would be the weight of a single coin.
Direction: The direction would be downwards, towards the table.

(3) The reaction of the 6th coin on the 7th:
According to Newton's third law, if the 7th coin exerts a force on the 6th coin, the 6th coin will also exert an equal but opposite force on the 7th coin.

Magnitude: The magnitude of the reaction force would be the same as the force exerted by the 7th coin on the 6th coin.
Direction: The direction would be upwards, away from the table.

It's important to note that the mass 'm' of each coin is not given, so it cannot be used to calculate specific values. However, by understanding the principles mentioned, you can determine the general behavior and relationships between the forces involved.