Question

The period of oscillation of a simple pendulum is $\mathrm { T } = 2 \pi \sqrt { \frac { \mathrm { L } } { \mathrm { g } } }$ . Measured value of L is 10 cm know to 1 mm accuracy and time for 100 oscillations of the pendulum is found to be 50 s using a wrist watch of 1 s resolution. What is the accuracy in the determination of g?

• A. (a) 2%
• A. (b) 3%
• A. (c) 4%
• A. (d) 5%

Answer 1

Potash alum is K2SO4.Al2(SO4)3.24H2O and so,

Al2(SO4)3 + 6NaOH $\longrightarrow$ 2Al(OH)3 ¯ (white) + 3Na2SO4 ; Al(OH)3 + OH– $\longrightarrow$ [Al(OH)4]– (soluble complex)