The young human eye can change focus from distance (infinity) to 6.7 cm from the eye in 350 milliseconds. This dramatic change in focal power of the eye of approximately 15 dioptres (the reciprocal of focal length in metres) occurs as a consequence of a reduction in zonular tension induced by ciliary muscle contraction. The amplitude of accommodation declines with age.
Singapore's close proximity to the equator means that its temperature and humidity remain relatively even throughout the year. Its average daytime temperatures are around 87 degrees Fahrenheit, varying only slightly between annual high temperatures of 90 degrees and low temperatures of 84 degrees.The hottest weather occurs in April. High humidity is a constant in Singapore, with an average relative humidity level of around 84 percent.On rainy days, the relative humidity remains at around 100 percent.ingapore's close proximity to the equator means that its temperature and humidity remain relatively even throughout the year. Its average daytime temperatures are around 87 degrees Fahrenheit, varying only slightly between annual high temperatures of 90 degrees and low temperatures of 84 degrees.
February is the hottest month in Singapore with an average temperature of 27Â°C (81Â°F) and the coldest is January at 26Â°C (79Â°F) with the most daily sunshine hours at 9 in September. The wettest month is December with an average of 269mm of rain.