In previous question, the time of flight of the body is

Options

A. 0.8s
B. 4.0s
C. 8.0s
D. 10 s

Explanation

To find the time of flight of a projectile launched with an initial velocity of \( \vec{v} = 3 \hat{i} + 4 \hat{j} \) m/s, we can follow these steps:

### Step 1: Identify the vertical component of the initial velocity
The vertical component of the initial velocity \( u_y \) is given as the coefficient of \( \hat{j} \) in the velocity vector. From the given vector:
\[ u_y = 4 \text{ m/s} \]

### Step 2: Use the formula for time of flight
The time of flight \( T \) for a projectile is given by the formula:
\[ T = \frac{2u_y}{g} \]
where \( g \) is the acceleration due to gravity. In this case, \( g = 10 \text{ m/s}^2 \).

### Step 3: Substitute the values into the formula
Now, substituting the values we have:
\[ T = \frac{2 \times 4 \text{ m/s}}{10 \text{ m/s}^2} \]

### Step 4: Calculate the time of flight
Calculating the above expression:
\[ T = \frac{8}{10} = 0.8 \text{ seconds} \]

### Conclusion
Thus, the time of flight of the body is \( 0.8 \) seconds.

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