Question

A particle moves in a circle of radius $0.5m$ at a speed that uniformly increases. Find the angular acceleration of particle if its speed changes from $2ms^{- 1}$ to $4ms^{- 1}$ in $4seconds$ ?

• A. $1$ $rads^{- 2}$
• B. $2rads^{- 2}$
• C. $4rads^{- 2}$
• D. $0rads^{- 2}$

Answer 1

Answer: (A)

The tangential acceleration of the particle is
$a_{t}=\frac{d v}{d t}=\frac{4.0 - 2.0}{4.0}$
$=0.5ms^{- 2}$
The angular acceleration is
$\alpha =\frac{a_{t}}{r}=\frac{0.5}{0.5}=1rads^{- 2}$