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Impurities
joseph rimiru answered the question on October 11, 2017 at 17:29
- A student found that a drop of methylated spirit on the back of the hand felt colder than a drop of water at...(Solved)
A student found that a drop of methylated spirit on the back of the hand felt colder than a drop of water at the same temperature. Explain.
Date posted: October 11, 2017. Answers (1)
- A heater rated 3.5 kw is used to raise the temperature of 5 kg of water through 70° C. Calculate the time required. (specific heat...(Solved)
A heater rated 3.5 kw is used to raise the temperature of 5 kg of water through 70⁰ C. Calculate the time required. (specific heat capacity of water is 4200 J/kg K). Give your answer in minutes.
Date posted: October 11, 2017. Answers (1)
- An immersion heater rated 900 w is placed in a liquid of mass 4 kg. It was switched on for 20 minutes and the temperature...(Solved)
An immersion heater rated 900 w is placed in a liquid of mass 4 kg. It was switched on for 20 minutes and the temperature of the liquid raised from 25°C to 35°C. Determine the specific heat capacity of the liquid
Date posted: October 11, 2017. Answers (1)
- A alloy of copper mass 4 kg and specific heat capacity 400 J/kg K initially at 91° is immersed in water at 20° C. if...(Solved)
A alloy of copper mass 4 kg and specific heat capacity 400 J/kg K initially at 91⁰ is immersed in water at 20⁰ C. if the final temperature is 21⁰C, determine the mass of water.(the specific heat capacity of water is 4200 J/kg K). give your answer to one decimal place.
Date posted: October 11, 2017. Answers (1)
- Some water of mass 4 kg, at a temperature of 100° is allowed to cool for 20 minutes. State the factors that determine its final...(Solved)
Some water of mass 4 kg, at a temperature of 100⁰ is allowed to cool for 20 minutes. State the factors that determine its final temperature.
Date posted: October 11, 2017. Answers (1)
- An electric kettle rated 2000 W takes 20 minutes to heat 30 kg of a liquid from 30° C to 45°C. (Solved)
An electric kettle rated 2000 W takes 20 minutes to heat 30 kg of a liquid from 30⁰ C to 45⁰C.
Date posted: October 11, 2017. Answers (1)
- Ice change to water at 0° C. 5 kg of ice and 5 kg of water at 0° were heated separately. Give a reason why...(Solved)
Ice change to water at 0⁰ C. 5 kg of ice and 5 kg of water at 0⁰ were heated separately. Give a reason why more heat energy is required to heat ice.
Date posted: October 11, 2017. Answers (1)
- A boy took 10 kg of water and raised its temperature to 90° C. He add m2 kg of water at 20° C and...(Solved)
A boy took 10 kg of water and raised its temperature to 90⁰ C. He add m2 kg of water at 20⁰ C and the mixture attained a temperature of 50⁰ C. Determine the value of m2. (Assume the containers did not get heated. Specific heat capacity of water = 4200Jkg^-1k^-1)
Date posted: October 11, 2017. Answers (1)
- A ball was moving in a horizontal circle of radius 0.4 m makes 16 revolution per second. Find its centripetal acceleration.(Solved)
A ball was moving in a horizontal circle of radius 0.4 m makes 16 revolution per second. Find its centripetal acceleration.
Date posted: October 10, 2017. Answers (1)
- Find the value of -30^0 C on the absolute temperature scale.(Solved)
Find the value of -30^0 C on the absolute temperature scale.
Date posted: October 10, 2017. Answers (1)
- A sample of water was found to boil above 1000 C. State two factors that could have led this observation.(Solved)
A sample of water was found to boil above 1000 C. State two factors that could have led this observation.
Date posted: October 10, 2017. Answers (1)
- A battery of e.m.f 12 v and negligible resistance is connected to a 8 ohms resistor. How much power is dissipated by the resistor?(Solved)
A battery of e.m.f 12 v and negligible resistance is connected to a 8 ohms resistor. How much power is dissipated by the resistor?
Date posted: October 10, 2017. Answers (1)
- Determine the resistance of a blow dryer rated 3000 w, 240 v.(Solved)
Determine the resistance of a blow dryer rated 3000 w, 240 v.
Date posted: October 10, 2017. Answers (1)
- Determine the resistance of a bulb rated 100 w, 240 v.(Solved)
Determine the resistance of a bulb rated 100 w, 240 v.
Date posted: October 10, 2017. Answers (1)
- Calculate the energy dissipated in 5 minutes if an electric bulb with a filament of resistance 360 ohms is connected to 240 v mains supply.(Solved)
Calculate the energy dissipated in 5 minutes if an electric bulb with a filament of resistance 360 ohms is connected to 240 v mains supply.
Date posted: October 10, 2017. Answers (1)
- An energy saving bulb rated 10 w, 240 v was used continuously for 1000 hours. Determine the energy consumed giving your answer in kilowatt hour....(Solved)
An energy saving bulb rated 10 w, 240 v was used continuously for 1000 hours. Determine the energy consumed giving your answer in kilowatt hour. (kwh)
Date posted: October 10, 2017. Answers (1)
- In waves there is the occurrence of interference. State the necessary conditions for this to occur.(Solved)
In waves there is the occurrence of interference. State the necessary conditions for this to occur.
Date posted: October 10, 2017. Answers (1)
- On carrying out an experiment it was found that a voltmeter of high resistance was more accurate compared to that of low resistance. State the...(Solved)
On carrying out an experiment it was found that a voltmeter of high resistance was more accurate compared to that of low resistance. State the reason.
Date posted: October 10, 2017. Answers (1)
- What is Nuclear fission?(Solved)
What is Nuclear fission?
Date posted: October 10, 2017. Answers (1)
- Define Nuclide(Solved)
Define Nuclide
Date posted: October 10, 2017. Answers (1)