Question 206: Motion in 2D & Vectors

Question

A stone tied to the end  of a string  of 1 m long  is whirled in a horizontal circle with a constant speed. If the stone makes 22 revoluations in 44 seconds, what  is the magnitude and direction of acceleration of the stone ?

Accepted Answer

$${a_r} = {\omega ^2}R\,$$ & $$\,{a_t} = {{dv} \over {dt}} = 0$$
or, ar= (2$$\pi $$n)2R = 4$$\pi ^2$$n
2
R
2
= $$4{\pi ^2}{\left( {{{22} \over {44}}} \right)^2}{\left( 1 \right)^2}$$
a
net
= a
r
= $${\pi ^2}$$ms
Ã¢ÂÂ2
and direction along the radius
towards the centre.

Answer

$${\pi ^2}\,$$ m s$$-$$2 and direction along the radius towards the centre

Answer

$${\pi ^2}\,$$ m s$$-$$2 and direction along the radius away from the centre

Answer

$${\pi ^2}\,$$ m s$$-$$2 and direction along the tangent to the circle

Answer

$${\pi ^2}\,$$/4 ms$$-$$2 and direction along the radius towards the centre.

Motion in 2D & Vectors

A stone tied to the end of a string of 1 m long is whirled in a horizontal circle with a constant speed. If the stone makes 22 revoluations in 44 seconds, what is the magnitude and direction of acceleration of the stone ?

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