The Summer solstice and a simple experiment      

The vertical sundial in the park was used to demonstrate the identification of the summer solstice on June 21st. The vertical sundial consists of a slit on a metallic sheet; the sunlight peeping through the slot sweeps across the dial indicating the time. Two pendulums were suspended from the ends of the slot so that they barely touch the ground. On 26th April it was noted that the shadow of the shadow of bobs coincided with the base. On 21st June, the shadow had shifted to South. The length of the shadow of the slot was 56cm. The length of the pendulum was 76 cm. Therefore the sun was at 36.4 degrees from the zenith on June 21st. This gives the latitude of Bangalore as 12.9 degrees. On April 26th the sunís declination was exactly 13 degrees, which is equal to the latitude. Hence the shadow was exactly coinciding with the base. The figures indicate the shadows of the pendulums on these dates

Waning phase of Venus captured by Dr. Nagaraj from Mysore      

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