(c) A body of mass 0.30 kg is made to perform simple harmonic motion with a speed of 2.50 m/s and an amplitude of 0.04 m.

i. Calculate the maximum velocity of the particle.
ii. Calculate the maximum acceleration of the particle.
iii. Calculate the energy associated with the motion.

(d) A small bob of mass [tex]$2.0 \times 10^{-2} kg$[/tex] oscillates as a simple pendulum with an amplitude of [tex]$5.0 \times 10^{-2} m$[/tex] and a period of 2 s.

Calculate the maximum velocity of the bob.



Answer :

Sure! Let's tackle each part of the question step-by-step:

### Part (c)

#### i. Maximum Velocity of the Particle
To find the maximum velocity ([tex]\(v_{\text{max}}\)[/tex]) of the particle in simple harmonic motion, we use the given speed value. For simplicity, we can directly use the provided speed as the maximum velocity:

[tex]\[ v_{\text{max}} = 2.505 \, \text{m/s} \][/tex]

#### ii. Maximum Acceleration of the Particle
The maximum acceleration ([tex]\(a_{\text{max}}\)[/tex]) in simple harmonic motion is given by [tex]\(a_{\text{max}} = \omega^2 \cdot \text{amplitude}\)[/tex], where [tex]\(\omega\)[/tex] is the angular frequency.

To find [tex]\(\omega\)[/tex], we use:

[tex]\[ \omega = \frac{v_{\text{max}}}{\text{amplitude}} \][/tex]

Given:
- [tex]\(v_{\text{max}} = 2.505 \, \text{m/s}\)[/tex]
- [tex]\(\text{amplitude} = 0.04 \, \text{m}\)[/tex]

Calculate [tex]\(\omega\)[/tex]:

[tex]\[ \omega = \frac{2.505}{0.04} \approx 62.625 \, \text{rad/s} \][/tex]

Now, calculate [tex]\(a_{\text{max}}\)[/tex]:

[tex]\[ a_{\text{max}} = \omega^2 \cdot \text{amplitude} = (62.625)^2 \cdot 0.04 \approx 156.876 \, \text{m/s}^2 \][/tex]

#### iii. Energy Associated with the Motion
The total mechanical energy ([tex]\(E\)[/tex]) in simple harmonic motion is given by:

[tex]\[ E = \frac{1}{2} k \cdot \text{amplitude}^2 \][/tex]

where [tex]\(k\)[/tex] is the spring constant. Using the relationship [tex]\(v_{\text{max}} = \omega \cdot \text{amplitude}\)[/tex] and [tex]\(\omega = \sqrt{\frac{k}{m}}\)[/tex], we can find [tex]\(k\)[/tex] as follows:

[tex]\[ v_{\text{max}}^2 = k/m \cdot \text{amplitude}^2 \implies k = \frac{m \cdot v_{\text{max}}^2}{\text{amplitude}^2} \][/tex]

Given:
- [tex]\(m = 0.30 \, \text{kg}\)[/tex]
- [tex]\(v_{\text{max}} = 2.505 \, \text{m/s}\)[/tex]
- [tex]\(\text{amplitude} = 0.04 \, \text{m}\)[/tex]

Calculate [tex]\(k\)[/tex]:

[tex]\[ k = \frac{0.30 \cdot (2.505)^2}{(0.04)^2} \approx 117.656 \, \text{N/m} \][/tex]

Now, calculate [tex]\(E\)[/tex]:

[tex]\[ E = \frac{1}{2} \cdot 117.656 \cdot (0.04)^2 \approx 0.941 \, \text{J} \][/tex]

### Part (d)

#### Calculate the Maximum Velocity of the Bob
The maximum velocity ([tex]\(v_{\text{max}}\)[/tex]) of the bob in simple harmonic motion is given by:

[tex]\[ v_{\text{max}} = \omega \cdot \text{amplitude} \][/tex]

First, we find the angular frequency [tex]\(\omega\)[/tex] using the period [tex]\(T\)[/tex]:

[tex]\[ \omega = \frac{2\pi}{T} \][/tex]

Given:
- [tex]\(T = 2.1 \, \text{s}\)[/tex]
- [tex]\(\text{amplitude} = 5.0 \times 10^{-2} \, \text{m}\)[/tex]

Calculate [tex]\(\omega\)[/tex]:

[tex]\[ \omega = \frac{2\pi}{2.1} \approx 2.994 \, \text{rad/s} \][/tex]

Now, calculate [tex]\(v_{\text{max}}\)[/tex]:

[tex]\[ v_{\text{max}} = 2.994 \cdot 0.05 \approx 0.150 \, \text{m/s} \][/tex]

Thus, the final results are:
- Maximum velocity of the particle (part c): [tex]\(2.505 \, \text{m/s}\)[/tex]
- Maximum acceleration of the particle: [tex]\(156.876 \, \text{m/s}^2\)[/tex]
- Energy associated with the motion: [tex]\(0.941 \, \text{J}\)[/tex]
- Maximum velocity of the bob (part d): [tex]\(0.150 \, \text{m/s}\)[/tex]