Get premium membership and access questions with answers, video lessons as well as revision papers.
a. This is to absorb as much heat as possible since dull surfaces are good absorbers of heat
b. Copper is a very good conductor of heat hence transfer much heat to the water being heated.
c. It is coiled to make its length bigger/ longer
d. To avoid heat loss from the solar heater
e. To trap the heat /wave from escaping from the collector plates/ have the greenhouse effect.
joseph rimiru answered the question on October 30, 2017 at 10:30
- A man's feet felt cold while standing on cement compare to a wooden floor. Explain(Solved)
A man's feet felt cold while standing on cement compare to a wooden floor. Explain.
Date posted: October 30, 2017. Answers (1)
- Which features of the clinical thermometer make it special?(Solved)
Which features of the clinical thermometer make it special?
Date posted: October 30, 2017. Answers (1)
- List three main feature of the common liquid-in-glass thermometer.(Solved)
List three main feature of the common liquid-in-glass thermometer.
Date posted: October 30, 2017. Answers (1)
- State four properties of a liquid that is suitable for use in a thermometer.(Solved)
State four properties of a liquid that is suitable for use in a thermometer.
Date posted: October 30, 2017. Answers (1)
- A mechanic wants to fit an iron ring tightly onto a steel rod of equal diameter to the inner diameter of the ring. Explain how...(Solved)
A mechanic wants to fit an iron ring tightly onto a steel rod of equal diameter to the inner diameter of the ring. Explain how this can be achieved.
Date posted: October 30, 2017. Answers (1)
- State and explain two disadvantages of anomalous expansion of water.(Solved)
State and explain two disadvantages of anomalous expansion of water.
Date posted: October 27, 2017. Answers (1)
- Explain briefly a mechanism by which heat is conducted through a metal.(Solved)
Explain briefly a mechanism by which heat is conducted through a metal.
Date posted: October 27, 2017. Answers (1)
- Force F acts on a body of mass M such that its velocity changes from u to v in time t. Derive from first principles...(Solved)
Force F acts on a body of mass M such that its velocity changes from u to v in time t. Derive from first principles the equation: F=ma.
Date posted: October 27, 2017. Answers (1)
- For a body to be at equilibrium under the action of parallel forces two conditions must be satisfied.
State one condition of equilibrium.(Solved)
For a body to be at equilibrium under the action of parallel forces two conditions must be satisfied.
State one condition of equilibrium.
Date posted: October 27, 2017. Answers (1)
- Explain why water stored in an earthen jar becomes cooler than the one which is stored in a metallic jar.(Solved)
Explain why water stored in an earthen jar becomes cooler than the one which is stored in a metallic jar.
Date posted: October 27, 2017. Answers (1)
- State and explain the effect of decrease in temperature on the surface tension.(Solved)
State and explain the effect of decrease in temperature on the surface tension.
Date posted: October 27, 2017. Answers (1)
- A spring extends by 2cm when a mass of 50g is hanged on it. What force is required to extend it by 2.5cm?(Solved)
A spring extends by 2cm when a mass of 50g is hanged on it. What force is required to extend it by 2.5cm?
Date posted: October 27, 2017. Answers (1)
- Why is the scald from steam more hurting than that of boiling water?(Solved)
Why is the scald from steam more hurting than that of boiling water?
Date posted: October 27, 2017. Answers (1)
- A driving gear wheel having 25 teeth engages with a second wheel with 100 teeth. If the gear system is 85% efficient, find the mechanical...(Solved)
A driving gear wheel having 25 teeth engages with a second wheel with 100 teeth. If the gear system is 85% efficient, find the mechanical advantage.
Date posted: October 27, 2017. Answers (2)
- What is the purpose of the pear- shaped cross section of a clinical thermometer.(Solved)
What is the purpose of the pear- shaped cross section of a clinical thermometer.
Date posted: October 27, 2017. Answers (1)
- Describe how microwaves are used in determining distances of objects as in the radar(Solved)
Describe how microwaves are used in determining distances of objects as in the radar
Date posted: October 27, 2017. Answers (1)
- The element of an electric hot plate has a resistance of 80Ohms. What is the energy dissipated when the element is kept on for 20...(Solved)
The element of an electric hot plate has a resistance of 80Ohms. What is the energy dissipated when the element is kept on for 20 minutes on a 240V supply
Date posted: October 27, 2017. Answers (1)
- A student stands at a distance 400m from a wall and claps two pieces of wood. After the first clap the student claps whenever an...(Solved)
A student stands at a distance 400m from a wall and claps two pieces of wood. After the first clap the student claps whenever an echo is heard from the wall. Another student starts a stopwatch at the first clap and stops it after the twentieth clap. The stopwatch records a time of 50 seconds. Find the speed of sound.
Date posted: October 27, 2017. Answers (1)
- Use the domain theory to explain how an unmagnetized piece of iron becomes magnetized when it is heated and then allowed to cool in a...(Solved)
Use the domain theory to explain how an unmagnetized piece of iron becomes magnetized when it is heated and then allowed to cool in a magnetized field.
Date posted: October 27, 2017. Answers (1)
- Explain why the e.m.f of a dry cell drops if a large current is drawn for a short time and then recovers if allowed to...(Solved)
Explain why the e.m.f of a dry cell drops if a large current is drawn for a short time and then recovers if allowed to rest.
Date posted: October 27, 2017. Answers (1)