Two springs of spring constants \(k_1\) and \(k_2\) are joined in series. The effective spring constant of the combination is given by:
1. \(\frac{k_1+k_2}{2}\)
2. \(k_1+k_2\)
3. \(\frac{k_1k_2}{k_1+k_2}\)
4. \(\sqrt{k_1k_2}{}\)
If two identical springs, each with a spring constant \(k,\) are connected in series, the new spring constant and time period will change by a factor of:
| 1. | \( \dfrac{1}{2},~ \sqrt{2} \) | 2. | \( \dfrac{1}{4},~ \sqrt{2} \) |
| 3. | \( \dfrac{1}{4},~ 2 \sqrt{2} \) | 4. | \( \dfrac{1}{2},~ 2 \sqrt{2} \) |
Two identical springs of spring constant \(k\) are attached to a block of mass \(m\) and to fixed supports as shown in the figure. When the mass is displaced from its equilibrium position on either side, it executes a simple harmonic motion. The period of oscillations is:
A spring having a spring constant of \(1200\) N/m is mounted on a horizontal table as shown in the figure. A mass of \(3\) kg is attached to the free end of the spring. The mass is then pulled sideways to a distance of \(2.0\) cm and released. The maximum acceleration of the mass is:
| 1. | \(6\) ms–2 | 2. | \(8\) ms–2 |
| 3. | \(3.3\) ms–2 | 4. | \(5.1\) ms–2 |
What is the period of oscillation of the block shown in the figure?
| 1. | \(2\pi \sqrt{\dfrac{M}{k}}\) | 2. | \(2\pi \sqrt{\dfrac{4M}{k}}\) |
| 3. | \(\pi \sqrt{\dfrac{M}{k}}\) | 4. | \(2\pi \sqrt{\dfrac{M}{2k}}\) |

A body mass m is attached to the lower end of a spring whose upper end is fixed. The spring has neglible mass. When the mass m is slightly pulled down and released, it oscillates with a time period of 3s. When the mass m is increased by 1 kg, the time period of oscillations becomes 5s. The value of m in kg is-
1.
2.
3.
4.
| 1. | \(\pi \sqrt{\dfrac{4 m}{5 k}}\) | 2. | \(\pi \sqrt{\dfrac{6 m}{5 k}}\) |
| 3. | \(\pi \sqrt{\dfrac{12m}{5 k}}\) | 4. | \(\pi \sqrt{\dfrac{8m}{5 k}}\) |