A block of weight 9.8N is placed on a table. The table surface exerts an upward force of 10 N on the block. Assume `g = 9.8 m//s^(2)`.

Options

A. The block exerts a force of 10N on the table
B. The block exerts a force of 19.8 N on the table
C. The block exerts a force of 9.8N on the table
D. The block has an upward acceleration

Answer

To solve the problem, we need to analyze the forces acting on the block placed on the table. Here’s a step-by-step breakdown:

### Step 1: Identify the Forces
The block has two main forces acting on it:
1. **Weight (W)**: This is the downward force due to gravity, which is given as 9.8 N.
2. **Normal Force (N)**: This is the upward force exerted by the table on the block, which is given as 10 N.

### Step 2: Draw a Free Body Diagram
We can visualize the forces acting on the block:
- Draw a downward arrow representing the weight (9.8 N).
- Draw an upward arrow representing the normal force (10 N).

### Step 3: Apply Newton's Second Law
According to Newton's second law, the net force acting on the block can be calculated as:
\[ F_{net} = N - W \]
Where:
- \( N = 10 \, \text{N} \) (upward force)
- \( W = 9.8 \, \text{N} \) (downward force)

### Step 4: Calculate the Net Force
Substituting the values into the equation:
\[ F_{net} = 10 \, \text{N} - 9.8 \, \text{N} = 0.2 \, \text{N} \]

### Step 5: Determine the Mass of the Block
Using the weight of the block to find its mass:
\[ W = mg \]
Where:
- \( W = 9.8 \, \text{N} \)
- \( g = 9.8 \, \text{m/s}^2 \)

Rearranging gives:
\[ m = \frac{W}{g} = \frac{9.8 \, \text{N}}{9.8 \, \text{m/s}^2} = 1 \, \text{kg} \]

### Step 6: Calculate the Acceleration
Now, we can find the acceleration of the block using the net force and mass:
\[ F_{net} = ma \]
Rearranging gives:
\[ a = \frac{F_{net}}{m} = \frac{0.2 \, \text{N}}{1 \, \text{kg}} = 0.2 \, \text{m/s}^2 \]

### Final Result
The acceleration of the block is \( 0.2 \, \text{m/s}^2 \).

---