#### Question

The bob of a simple pendulum of length 1 m has mass 100 g and a speed of 1.4 m/s at the lowest point in its path. Find the tension in the string at this instant.

#### Solution

Given:

Mass of the bob = m = 100 gm = 0.1 kg

Length of the string = r = 1 m

Speed of bob at the lowest point in its path = 1.4 m/s

Let T be the tension in the string.

From the free body diagram,

we get :

\[\text{T = mg }+ \frac{\text{mv}^2}{\text{r}}\]

\[ = \left( \frac{1}{10} \right) \times 9 . 8 + \frac{(1 . 4 )^2}{10}\]

\[ = 0 . 98 + 0 . 196\]

\[ = 1 . 176 \approx 1 . 2 \text{N}\]

Is there an error in this question or solution?

Solution The Bob of a Simple Pendulum of Length 1 M Has Mass 100 G and a Speed of 1.4 M/S at the Lowest Point in Its Path. Find the Tension in the String at this Instant. Concept: Circular Motion.