Amount of heat and UV radiation emitted. Answer: Measure Ambient Light … True or False – if false give the correct statement. Question 5. I have measured power of a UV light source in Watts whose spectrum spans from 360 to 375 nm. Answer: What is luminous Intensity? What is luminous intensity? The angle at which the rays from the sun hit the Earth determines this intensity. (c) Assertion is true, but reason is false. Mark the correct choice as: What are the differences between Plane angle and solid angle? Question 5. The basic way to calculate UV dose from a UVC 15Watt bulb? He told, he was affected by a fever of 100°C and went to a hospital for treatment. Answer: The LS126C UV light intensity meter also has an intelligent statistical function, which displays real-time value, maximum value, minimum value, average value, measurement duration, date and time. Answer: Answer: Normal temperature of the human body is between 98.4° F and 98.6° F. Question 7. Answer: (c) Error Answer: These clocks are activated by ‘electronic oscillations’, which are controlled by a ‘quartz crystal’. Instead, if accuracy matters, I'd use a line source model - I'll outline it here if it helps; I derived a model for this as part of my PhD in the context of UV phototherapy, as the lamps used in treatment are typically ~ 1.75 metres long and the patient is right on top of them, so point source was a no go. Answer: Amount of substance gives the number of particles present in the substance. Intensity … Mention the SI unit of luminous flux. (b) A number and a unit, Question 3. I want to find the Irradiance (Watts/m2) from the given power in the given spectral range to compare with the irradiance of the UV of this range in 1 Sun (AM 1.5). Luminous intensity typically is represented by the symbol I ν, where the subscript ν denotes a photometric quantity, and its unit is the candela, an SI base unit (1 cd = 1 lumen/steradian, where the … Given that a UV bulb with 2x15 Watt, wavelength of 365nm, the intensity at 15cm is 2300uW/cm2. Or the distribution of wavelengths and frequencies. VII. This value is the intensity at (15cm) and the intensity change with the distance. If a light source emits light with equal intensity towards all directions, total luminous flux emitted by the light is. Answer: Define electric current. (c) International symbol of units A number of genes are activated by UV, others are down-regulated, and the phosphorylatio... Join ResearchGate to find the people and research you need to help your work. Tell me more about spectra. and different types of other complex formula  that I don't quite understand). Question 6. Correct statement: I want to use it for microbial inactivation. Please mention the source of UV-B. Bhd., Subang Jaya, Malaysia, Dose modeling in ultraviolet phototherapy. Question 1. (b) Derived quantities. Given that a UV bulb with 2x15 Watt, wavelength of 365nm, the intensity at 15cm is 2300uW/cm2. Write a note on approximation. Candela (cd). In SI system the units are precisely defined and have the same value everywhere. Operating parameters of powerful UV and vacuum ultraviolet (VUV) excilamps with different discharge geometry excited by capacitive discharge, barrier discharge, glow discharge, and UV-preionized discharge were investigated. As Urszula mentions, you're seemingly looking for irradiance rather than intensity, though the convention on radiometric units if often sloppy between fields! (d) None of the above To calculate irradiance, this depends on your source; if it is just a 'perfect' bulb, then you can in theory use a point source. In your case to find out the irradiance at 3 cm distance more data are needed (first of all the size of the source, the radiance pattern). How many base quantities are there? It is measured at the longitude of zero degree. If it is wrong, try to make him to understand his mistake. If grow lights produce a lot of UV light (such as LEC), stay on the lower side of this range 70,000 – 85,000 lux – a lot of light, some strains thrive at this light level, but some plants (especially auto-flowering and Indica strains) lose their top leaves early under this light intensity. Question 1. (d) SI (c) Assertion is true, but reason is false How to calculate UV Irradiance (W/m2) over a range of wavelengths provided power (in watts) is known? Answer: (d) professional Precision : Precision is the closeness of two or more measurements to each other. Answer: Reason : One radian is the angle subtended at the centre of a circle by an arc of length equal to its radius. 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