A bird of mass 0.1 kg rising vertically with an acceleration `0.2 ms^(-2)`. The muscular force exerted by it is `(g=9.8 ms^(-2))`
(a) 1 Newton
(b) 9.8 kg,wt
(c ) 1/9.8 kg.wt
(d) 980 newtons.

Options

A. a is correct
B. a and b are correct
C. a and c are correct
D. b and d are correct

Answer

To solve the problem, we need to find the muscular force exerted by the bird while it is rising vertically with a given acceleration. We will use Newton's second law of motion, which states that the net force acting on an object is equal to the mass of the object multiplied by its acceleration.

### Step-by-Step Solution:

1. **Identify the given values:**
- Mass of the bird, \( m = 0.1 \, \text{kg} \)
- Acceleration, \( a = 0.2 \, \text{m/s}^2 \)
- Acceleration due to gravity, \( g = 9.8 \, \text{m/s}^2 \)

2. **Calculate the weight of the bird:**
The weight \( W \) of the bird can be calculated using the formula:
\[ W = mg \]
Substituting the values:
\[ W = 0.1 \, \text{kg} \times 9.8 \, \text{m/s}^2 = 0.98 \, \text{N} \]

3. **Apply Newton's second law:**
According to Newton's second law, the net force \( F \) acting on the bird is given by:
\[ F = ma \]
The net force acting on the bird when it is moving upwards is the difference between the muscular force \( F_m \) exerted by the bird and its weight:
\[ F_m - W = ma \]
Rearranging gives:
\[ F_m = W + ma \]

4. **Substitute the values:**
Now substituting the values we calculated:
\[ F_m = 0.98 \, \text{N} + (0.1 \, \text{kg} \times 0.2 \, \text{m/s}^2) \]
\[ F_m = 0.98 \, \text{N} + 0.02 \, \text{N} = 1.00 \, \text{N} \]

5. **Conclusion:**
The muscular force exerted by the bird is \( 1.00 \, \text{N} \).

### Answer:
The muscular force exerted by the bird is **1 Newton** (Option a).