Question

5. If the velocity (in m/s) of a particle is given by 4.0 i + 5.0tſ, then the magnitude of its acceleration (in m/s?) e is a. 4 d. - 4 b. - 5 c. 0​

Answer 1

Explanation:

The velocity of the particle is given as $v=4.0{\hat i}+5.0t \hat j$ m/s.

Acceleration is defined as derivative of velocity, $a =\frac{dv}{dt}$

⇒$a=\frac{d(4\hat i+5t\hat j)}{dt} = 5\hat j$

The first term in the derivative is zero because its a constant. Hence acceleration of the particle is $5 m/s^2$ in y direction. 5 is the magnitude of acceleration.