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1. Addition of impurities to water
2. Heating water under high pressures
johnmulu answered the question on February 15, 2017 at 13:52
- Water of mass 3 kg, at a temperature of 90oC is allowed to cool for 10 minutes. state two factors that determine the final temperature. (Solved)
Water of mass 3 kg, at a temperature of 90oC is allowed to cool for 10 minutes. State two factors, other than humidity, that determine the final temperature.
Date posted: February 15, 2017. Answers (1)
- Ice changes to water at 0oC. Equal masses of the ice and water at 0oC are each heated to 1oC. Give a reason why more heat energy is required to heat the ice(Solved)
Ice changes to water at 0oC. Equal masses of the ice and water at 0oC are each heated to 1oC. Give a reason why more heat energy is required to heat the ice.
Date posted: February 15, 2017. Answers (1)
- Describe the experiment to determine the specific heat capacity, c, of a block of aluminium with two holes drilled in it(Solved)
Describe the experiment to determine the specific heat capacity, c, of a block of aluminium with two holes drilled in it, to accommodate a thermometer and an electric immersion heater.
Date posted: February 15, 2017. Answers (1)
- Distinguish between heat capacity and specific heat capacity of a body(Solved)
Distinguish between heat capacity and specific heat capacity of a body.
Date posted: February 15, 2017. Answers (1)
- A 4 ohm resistor is connected in series to a battery of e.m.f. 6 V and negligible internal resistance. Determine the power dissipated by the resistor. (Solved)
A 4 ohm resistor is connected in series to a battery of e.m.f. 6 V and negligible internal resistance. Determine the power dissipated by the resistor.
Date posted: February 15, 2017. Answers (1)
- A current I flowing through a wire of resistance R was increased seven times. Determine the factor by which the rate of heat production was increased.(Solved)
A current I flowing through a wire of resistance R was increased seven times. Determine the factor by which the rate of heat production was increased.
Date posted: February 15, 2017. Answers (1)
- A heating coil is rated 100 W, 240 V. At what rate would it dissipate energy it is connected to a 220 V supply(Solved)
A heating coil is rated 100 W, 240 V. At what rate would it dissipate energy it is connected to a 220 V supply
Date posted: February 15, 2017. Answers (1)
- A hair drier is rated 2500W, 240V. Determine its resistance(Solved)
A hair drier is rated 2500W, 240V. Determine its resistance
Date posted: February 15, 2017. Answers (1)
- An electric heater is connected to the mains supply. A fault in the mains reduces the supply potential slightly(Solved)
An electric heater is connected to the mains supply. A fault in the mains reduces the supply potential slightly. Explain the effect on the rate of heating of the heater.
Date posted: February 15, 2017. Answers (1)
- An electric bulb is rated 75W, 240V. Determine the resistance of the bulb(Solved)
An electric bulb is rated 75W, 240V. Determine the resistance of the bulb
Date posted: February 15, 2017. Answers (1)
- An electric bulb with a filament of resistance 480 ohms is connected to a 240 V mains supply. Determine the energy dissipated in 2 minutes(Solved)
An electric bulb with a filament of resistance 480 ohms is connected to a 240 V mains supply. Determine the energy dissipated in 2 minutes
Date posted: February 15, 2017. Answers (1)
- A 60 W bulb is used continuously for 36 hours. Determine the energy consumed. Give your answer in kilowatt hour (kWh)(Solved)
A 60 W bulb is used continuously for 36 hours. Determine the energy consumed. Give your answer in kilowatt hour (kWh)
Date posted: February 15, 2017. Answers (1)
- An electric heater rated 240 V, 3000 W is to be connected to a 240 V mains supply, through a 10 A fuse.Determine whether the fuse is suitable or not(Solved)
An electric heater rated 240 V, 3000 W is to be connected to a 240 V mains supply, through a 10 A fuse. Determine whether the fuse is suitable or not
Date posted: February 15, 2017. Answers (1)
- When a current of 2.0 A flows in resistor for 10 minutes, 15, 000 joules of electrical energy is dissipated. Determine the voltage across the resistor(Solved)
When a current of 2.0 A flows in resistor for 10 minutes, 15, 000 joules of electrical energy is dissipated. Determine the voltage across the resistor.
Date posted: February 15, 2017. Answers (1)
- State three factors that affect the capacitance of a parallel plate capacitor(Solved)
State three factors that affect the capacitance of a parallel plate capacitor
Date posted: February 15, 2017. Answers (1)
- State the effect of decreasing the distance between the plates of a parallel plate capacitor on the capacitance(Solved)
State the effect of decreasing the distance between the plates of a parallel plate capacitor on the capacitance.
Date posted: February 15, 2017. Answers (1)
- A positively charged electroscope gets discharged when the cap is touched with a finger.(Solved)
Explain how a positively charged electroscope gets discharged when the cap is touched with a finger.
Date posted: February 15, 2017. Answers (1)
- Light from a lamp falls on the cap of a negatively charged electroscope. It is observed that the divergence of the leaf decreases(Solved)
Light from a lamp falls on the cap of a negatively charged electroscope. It is observed that the divergence of the leaf decreases. Explain the observation
Date posted: February 15, 2017. Answers (1)
- In some petrol engines where sparks plugs are used, a capacitor is connected to the distributor suggest the function of the capacitor(Solved)
In some petrol engines where sparks plugs are used, a capacitor is connected to the distributor suggest the function of the capacitor.
Date posted: February 14, 2017. Answers (1)
- Name two factors other than tension, which determine the frequency of sound from a stretched wire at room temperature(Solved)
Name two factors other than tension, which determine the frequency of sound from a stretched wire at room temperature.
Date posted: February 14, 2017. Answers (1)