Question 169: Motion in 2D & Vectors

Question

The x and y coordinates of the particle at any time are x = 5t $$-$$ 2t2 and y = 10t respectively,  where x and y are in metres and t in seconds. The acceleration of the particle at t = 2 s is

Accepted Answer

x = 5t $$-$$ 2t
2
and y = 10t
$${{dx} \over {dt}}$$ = 5 - 4t, $${{dy} \over {dt}}$$ = 10
$$ 	herefore $$ v
x
= 5 - 4t, v
y
= 10
$${{d{v_x}} \over {dt}}$$ = - 4, $${{d{v_y}} \over {dt}}$$ = 0
$$ 	herefore $$ $${a_x}$$ = - 4, $${a_y}$$ = 0
$$\overrightarrow a  = {a_x}\widehat i + {a_y}\widehat j$$ = $$ - 4\widehat j$$ m/s
2
$$ 	herefore $$ Acceleration of the particle at t = 2 s is - 4 m/s
2

Answer

5 m s$$-$$2

Answer

$$-$$4 m s$$-$$2

Answer

$$-$$8 m s$$-$$2

Answer

0

Motion in 2D & Vectors

The x and y coordinates of the particle at any time are x = 5t $-$ 2t2 and y = 10t respectively, where x and y are in metres and t in seconds. The acceleration of the particle at t = 2 s is

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