A body is projected up with a velocity 50 `ms^(-1)` after one second if acceleration due to gravity disappears then body

Options

A. floats in air
B. continue to move up with constant velocity
C. continue to move up with acceleration
D. goes up and falls down

Answer

To solve the problem step by step, let's analyze the situation described:

### Step 1: Understand the Initial Conditions
A body is projected upwards with an initial velocity \( u = 50 \, \text{m/s} \). The acceleration due to gravity \( g \) acts downwards and is approximately \( 10 \, \text{m/s}^2 \).

### Step 2: Calculate the Velocity After 1 Second
Using the equation of motion:
\[ v = u - g \cdot t \]
where:
- \( v \) is the final velocity after time \( t \),
- \( u = 50 \, \text{m/s} \) (initial velocity),
- \( g = 10 \, \text{m/s}^2 \) (acceleration due to gravity),
- \( t = 1 \, \text{s} \) (time).

Substituting the values:
\[ v = 50 \, \text{m/s} - (10 \, \text{m/s}^2 \cdot 1 \, \text{s}) = 50 \, \text{m/s} - 10 \, \text{m/s} = 40 \, \text{m/s} \]

### Step 3: Analyze the Situation After 1 Second
After 1 second, it is stated that the acceleration due to gravity disappears. This means that there is no longer any force acting on the body. The body is now in a state of free motion with a constant velocity.

### Step 4: Determine the Motion of the Body
Since there is no acceleration acting on the body (net force is zero), the body will continue to move with the last calculated velocity of \( 40 \, \text{m/s} \) upwards. According to Newton's first law of motion, an object in motion will remain in motion at a constant velocity unless acted upon by an external force.

### Conclusion
The body will continue to move upwards with a constant velocity of \( 40 \, \text{m/s} \).

### Final Answer
The correct option is: **The body will continue to move up with constant velocity.**

---