Question 180: Motion in 2D & Vectors

Question

A particle has initial velocity $$\left( {2\overrightarrow i  + 3\overrightarrow j } \right)$$ and acceleration $$\left( {0.3\overrightarrow i  + 0.2\overrightarrow j } \right)$$. The magnitude of velocity after  10 seconds will be

Accepted Answer

$$\overrightarrow P $$ = vector sum = $$\overrightarrow A  + \overrightarrow B $$
$$\overrightarrow Q $$ = Vector differences = $$\overrightarrow A  - \overrightarrow B $$
Since $$\overrightarrow P $$ and $$\overrightarrow Q $$ are perpendicular
$$ 	herefore $$ $$\overrightarrow P .\overrightarrow Q  = 0 \Rightarrow \left( {\overrightarrow A  + \overrightarrow B } ight).\left( {\overrightarrow A  - \overrightarrow B } ight) = 0$$
$$ \Rightarrow {A^2} = {B^2} = \left| {\overrightarrow A } ight| = \left| {\overrightarrow B } ight|$$

Answer

$$9\sqrt 2 $$

Answer

$$5\sqrt 2 $$

Answer

5 units

Answer

9 units

Motion in 2D & Vectors

A particle has initial velocity $\left( {2\overrightarrow i + 3\overrightarrow j } \right) and acceleration \left( {0.3\overrightarrow i + 0.2\overrightarrow j } \right)$. The magnitude of velocity after 10 seconds will be

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