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Water has an unusual expansion. Air space is left to provide room for expansion when temperature falls below 4oC.
johnmulu answered the question on February 18, 2017 at 05:29
- When temperature of water reaches its boiling point, bubbles rise to the surface....(Solved)
When temperature of water reaches its boiling point, bubbles rise to the surface
i) State what is contained in the bubbles
ii) State the reason why bubbles rise to the surface only at the boiling point.
Date posted: February 18, 2017. Answers (1)
- Why it is advisable to use a pressure cooker for cooking at high altitudes (Solved)
Explain why it is advisable to use a pressure cooker for cooking at high altitudes
Date posted: February 18, 2017. Answers (1)
- State two factors that affect the boiling point of a liquid.(Solved)
Name two factors that affect the boiling point of a liquid.
Date posted: February 18, 2017. Answers (1)
- Define the term heat capacity(Solved)
Define the term heat capacity
Date posted: February 18, 2017. Answers (1)
- Water is known to boil at 100oC. A student heated some water and noticed that it boiled at 101oC. State two possible reasons for this observation. (Solved)
Water is known to boil at 100oC. A student heated some water and noticed that it boiled at 101oC. State two possible reasons for this observation.
Date posted: February 18, 2017. Answers (1)
- Stat two factors that affect the melting point of ice(Solved)
Stat two factors that affect the melting point of ice.
Date posted: February 18, 2017. Answers (1)
- What is meant by specific latent heat of fusion of a substance?(Solved)
Define specific latent heat of fusion of a substance.
Date posted: February 18, 2017. Answers (1)
- Explain why a drop of methylated spirit on the back of the hand feels colder than a drop of water at the same temperature.(Solved)
Explain why a drop of methylated spirit on the back of the hand feels colder than a drop of water at the same temperature.
Date posted: February 15, 2017. Answers (1)
- What is meant by 'Specific latent heat of vaporazation'.(Solved)
State what is meant by the term 'Specific latent heat of vaporazation'.
Date posted: February 15, 2017. Answers (1)
- State two factors that would raise the boiling point of water to above 100oC(Solved)
State two factors that would raise the boiling point of water to above 100oC
Date posted: February 15, 2017. Answers (1)
- 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)