Question 74: Motion in 1D

Question

A particle moves from the point $$\left( {2.0\widehat i + 4.0\widehat j} \right)$$ m, at t = 0, with an initial velocity $$\left( {5.0\widehat i + 4.0\widehat j} \right)$$ ms$$-$$1. It is acted upon by a constant force which produces a constant acceleration $$\left( {4.0\widehat i + 4.0\widehat j} \right)$$ ms$$-$$2.  What is the distance of the particle from the origin at time 2 s?

Accepted Answer

$$\overrightarrow S  = \left( {5\widehat i + 4} \right)2 + {1 \over 2}\left( {4\widehat i + 4\widehat j} \right)4$$
$$ = 10\widehat i + 8\widehat j + 8\widehat i + 8\widehat j$$
$$\overrightarrow {{r_f}}  - \overrightarrow {{r_i}}  = 18\widehat i + 16\widehat j$$
$$\overrightarrow {{r_f}}  = 20\widehat i + 20\widehat j$$
$$\left| {\overrightarrow {{r_f}} } \right| = 20\sqrt 2 $$

Answer

15 m

Answer

$$20\sqrt 2 $$ m

Answer

$$10\sqrt 2 $$ m

Answer

5 m

Motion in 1D

Choose the correct answer: