Question

a stone is tied to an end of a string 80cm long is whirled in a horizontal circle with a constant speed if the stone makes 14 revolution in 25 seconds what is the magnitude of velocity of stone​

Answer 1

Answer:

Explanation:

Length of string = 80cm =0.8m

Stone makes 14 revolutions in 25sec.

Hence, stone makes 14/25 revolution in 1 sec

e.g frequency = 14/25 sec^-1

We know,

Angular speed (ω)= 2π× frequency

= 2π × 14/25

= 28π/25 rad/sec

Now, acceleration (a) = ω²r

where r is the radius { length of string}

Acceleration = 0.8 × {28π/25}²

= 9.91 m/s²

Answer 2

Answer:

Explanation:

Frequency f=14/25 Hz

Angular velocity ω=2πf=  2×14π/25 rad/s=3.52rad/s

Acceleration is a=ω^2  r=(3.52 )^2 ×0.8=9.9m/s  

The direction is along the radius at every point towards the centre.