Get premium membership and access questions with answers, video lessons as well as revision papers.
Ice is a poor conductor of heat and less dense than water. During winter, ice floats and insulates the water under it. Below the frozen layer, the water remains in its liquid state and does not freeze. Also, oxygen is trapped beneath the layer of ice. This makes it possible for aquatic animals to survive during winter.
chrispohmomanyi answered the question on September 16, 2017 at 18:39
- Define the following terms as applied to curved mirrors. (a) Principal axis. (b) Centre of curvature(c) Principal focus(Solved)
Define the following terms as applied to curved mirrors.
a) Principal axis.
b) Centre of curvature.
c) Principal focus.
Date posted: September 16, 2017. Answers (1)
- Differentiate between the images formed by a convex mirror and a pinhole camera(Solved)
Differentiate between the images formed by a convex mirror and a pinhole camera
Date posted: September 16, 2017. Answers (1)
- State three properties of a liquid used in the thermometer(Solved)
State three properties of a liquid used in the thermometer
Date posted: September 16, 2017. Answers (1)
- Distinguish between cohesive and adhesive forces.(Solved)
Distinguish between cohesive and adhesive forces.
Date posted: September 16, 2017. Answers (1)
- A form two student in Afraha High school had two identical metal cans. Can A was painted dull black
while B was shinny. She fitted on...(Solved)
A form two student in Afraha High school had two identical metal cans. Can A was painted dull black
while B was shinny. She fitted on each of them a thermometer through the lids. She added equal
volumes of hot water at 70°c simultaneously. State and explain the observation made after 20
minutes.
Date posted: September 16, 2017. Answers (1)
- When mercury in a glass thermometer is used to measure the temperature of hot water, it is observed
that the mercury level first drops before beginning...(Solved)
When mercury in a glass thermometer is used to measure the temperature of hot water, it is observed
that the mercury level first drops before beginning to rise. Explain.
Date posted: September 16, 2017. Answers (1)
- A metal ball is cooled.State how the density of the ball will be affected(Solved)
A metal ball is cooled, state how the density of the ball will be affected
Date posted: September 16, 2017. Answers (1)
- A pipe of diameter 8.4cm is connected to another pipe of diameter 3.5cm. The speed of the water in
the bigger pipe is 1.8m/s. Find...(Solved)
A pipe of diameter 8.4cm is connected to another pipe of diameter 3.5cm. The speed of the water in
the bigger pipe is 1.8m/s. Find the speed of the water in the smaller pipe
Date posted: September 16, 2017. Answers (1)
- Explain how air enters the barrel of a Bunsen burner when the gas supply is opened.(Solved)
Explain how air enters the barrel of a Bunsen burner when the gas supply is opened.
Date posted: September 16, 2017. Answers (1)
- Explain how dynamic lift of the aeroplane is caused by the wings (Solved)
Explain how dynamic lift of the aeroplane is caused by the wings
Date posted: September 16, 2017. Answers (1)
- Define the term streamline flow. (Solved)
Define the term streamline flow.
Date posted: September 16, 2017. Answers (1)
- In an experiment to determine the specific latent heat of water, steam of 100°C was passed into water
Contained in a well lagged copper calorimeter....(Solved)
In an experiment to determine the specific latent heat of water, steam of 100⁰C was passed into water
Contained in a well lagged copper calorimeter. The following measurements were made:
-Mass of calorimeter =40g
-Mass of water + calorimeter = 135g.
-Final mass of calorimeter + water +condensed steam =148g
-Final temperature of the mixture =52⁰C.
Given that specific heat capacity of water = 4200Jkg^-1 k^-1
Specific heat capacity of copper = 390Jkg^-1 k^-1.
Determine the:
i)Mass of condensed steam
ii)The heat gained by the calorimeter and water if the initial temperature of the calorimeter and water
is 24⁰C
iii)Given that LV is the specific latent heat of vaporization of steam, write an expression for the heat
given out by steam.
iv)Determine the value of LV in (iii) above.
v)State the assumption made in the experiment.
Date posted: September 16, 2017. Answers (1)
- Explain how heat loss by radiation is minimized in a vacuum flask. (Solved)
Explain how heat loss by radiation is minimized in a vacuum flask.
Date posted: September 16, 2017. Answers (1)
- State one factor which affects stability of objects.(Solved)
State one factor which affects stability of objects.
Date posted: September 16, 2017. Answers (1)
- A meter rule is balanced by masses of 18g and 12g suspended from its ends. Find the position of its pivot point.(Solved)
A meter rule is balanced by masses of 18g and 12g suspended from its ends. Find the position of its pivot point.
Date posted: September 16, 2017. Answers (1)
- The volume of a fixed mass of gas collected at 73°C is 0.04m³ at normal atmospheric pressure. Determine the volume when the temperature drops to...(Solved)
The volume of a fixed mass of gas collected at 73⁰C is 0.04m³ at normal atmospheric pressure. Determine the volume when the temperature drops to 10⁰C at the same pressure.
Date posted: September 16, 2017. Answers (1)
- Explain why convection currents in gases are set up much faster than convection currents in liquids. (Solved)
Explain why convection currents in gases are set up much faster than convection currents in liquids.
Date posted: September 16, 2017. Answers (1)
- In an experiment to estimate the size of a molecule of olive oil, a drop of oil of volume 0.24mm³ was placed on a clean...(Solved)
In an experiment to estimate the size of a molecule of olive oil, a drop of oil of volume 0.24mm³ was placed on a clean water surface. The oil spread into a patch of area 4.2 x 10⁴mm². Estimate the size of a molecule of olive oil and express your answer in meters.
Date posted: September 16, 2017. Answers (1)
- Explain how aquatic animals and plants survive in a lake whose top layer is ice at 0oC.(Solved)
Explain how aquatic animals and plants survive in a lake whose top layer is ice at 0oC.
Date posted: September 16, 2017. Answers (1)
- Explain why the smell of a rotting body is very strong when the sun is hot as compared to early in the morning.(Solved)
Explain why the smell of a rotting body is very strong when the sun is hot as compared to early in the morning.
Date posted: September 16, 2017. Answers (1)