Question 188: Motion in 2D & Vectors

Question

A particle has initial velocity $$\left( {3\widehat i + 4\widehat j} \right)$$ and has acceleration $$\left( {0.4\widehat j + 0.3\widehat j} \right).$$ Its speed after 10 s is

Accepted Answer

$$\overrightarrow u  = 3\widehat i + 4\widehat j$$,  $$\overrightarrow a  = 0.4\widehat i + 0.3\widehat j$$
$$ \Rightarrow {u_x} = 3\,units,\,{u_y} = 4\,units$$
$${a_x} = 0.4\,units,\,{a_y} = 0.3\,units$$
$$ 	herefore $$ v
x
= u
x
+ a
x
$$ 	imes $$ 10 = 3 + 4 = 7 units
and v
y
= 4 + 0.3 $$ 	imes $$ 10 = 4 + 3 = 7 units
$$ 	herefore v = \sqrt {v_x^2 + v_y^2}  = 7\sqrt 2$$ units

Answer

7 units

Answer

$$7\sqrt 2 $$ units

Answer

8.5 units

Answer

10 units

Motion in 2D & Vectors

A particle has initial velocity $\left( {3\widehat i + 4\widehat j} \right) and has acceleration \left( {0.4\widehat j + 0.3\widehat j} \right).$ Its speed after 10 s is

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