A force of 10 Newton acts on a body of mass 20 kg for 10 seconds. Change in its momentum is

Options

A. `50 km-m//s`
B. `100 kg-m//s`
C. `300kg-ms`
D. `1000kg-m//s`

Explanation

To solve the problem, we need to calculate the change in momentum of a body when a force is applied to it. The change in momentum can be calculated using the impulse-momentum theorem, which states that the impulse applied to an object is equal to the change in momentum of that object.

### Step-by-Step Solution:

1. **Identify the Given Data:**
- Force (F) = 10 Newtons
- Mass (m) = 20 kg (not directly needed for this calculation)
- Time interval (Δt) = 10 seconds

2. **Understand the Concept of Impulse:**
- Impulse (J) is defined as the product of force and the time duration for which the force acts. Mathematically, it is expressed as:
\[ J = F \times \Delta t \]

3. **Calculate the Impulse:**
- Substitute the values of force and time into the impulse formula:
\[ J = 10 \, \text{N} \times 10 \, \text{s} = 100 \, \text{N·s} \]

4. **Relate Impulse to Change in Momentum:**
- According to the impulse-momentum theorem, the impulse is equal to the change in momentum (Δp):
\[ \Delta p = J \]
- Therefore, we have:
\[ \Delta p = 100 \, \text{N·s} \]

5. **Convert Units (if necessary):**
- Note that 1 N·s is equivalent to 1 kg·m/s. Thus:
\[ \Delta p = 100 \, \text{kg·m/s} \]

6. **Final Answer:**
- The change in momentum is:
\[ \Delta p = 100 \, \text{kg·m/s} \]

### Conclusion:
The change in momentum of the body is **100 kg·m/s**.

---