A particle is moving eastwards with a velocity of $5\, m / s$. In $10\, s$ the velocity changes to $5\, m / s$ northwards. The average acceleration in this time is
- zero
- $\frac{1}{\sqrt 2} m/s^2$ towards north-east
- $\frac{1}{\sqrt 2} m/s^2$ towards north-west
- $\frac{1}{2} m/s^2$ towards north
The Correct Option is C
Solution and Explanation
$ \Delta v = 5 \sqrt 2 m/s$ in north-west direction.
$a_av = \frac{5 \sqrt 2}{10}=\frac{1}{\sqrt 2} m/s^2$ (in north-west direction)
$\therefore$ Correct option is (c).
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Concepts Used:
Acceleration
In the real world, everything is always in motion. Objects move at a variable or a constant speed. When someone steps on the accelerator or applies brakes on a car, the speed of the car increases or decreases and the direction of the car changes. In physics, these changes in velocity or directional magnitude of a moving object are represented by acceleration.
