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प्रश्न
A disc rotates about its axis with a constant angular acceleration of 4 rad/s2. Find the radial and tangential accelerations of a particle at a distance of 1 cm from the axis at the end of the first second after the disc starts rotating.
उत्तर
Angular acceleration of the disc,
\[\alpha = 4\text{ rad/s}^2\]
Distance of the particle from the axis of rotation,
\[r = 1 cm = 0 . 01 m\]
\[\text{So, }\omega = \alpha t = 4\text{ rad/s}............ (t = 1 s)\]
Radial acceleration,
\[\alpha_r = \omega^2 r = 4^2 \times 0 . 01\]
\[= 0 . 16 m/ s^2 = 16 cm/ s^2 \]
Tangential acceleration,
\[\alpha_T = \alpha r = 0 . 04 m/ s^2 \]
\[= 4 cm/ s^2\]
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