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Applications of radiation
1. Electric kettles have a chrome coat to reduce radiation.
2. Electric iron are silver coated to minimize radiation.
3. Green houses use radiation (heat trap) to grow crops.
4. Clouds reflect radiation back to the earth hence cloudy nights are warmer than clear
nights.
Moraa orina answered the question on April 5, 2018 at 06:33
- State the applications of conductors(Solved)
State the applications of conductors
Date posted: April 5, 2018. Answers (1)
- Starting a car with 12 volts battery is better than 12 dry cells in series.Explain(Solved)
Starting a car with 12 volts battery is better than 12 dry cells in series.Explain
Date posted: April 5, 2018. Answers (1)
- The master cylinder piston in a car braking system has a diameter of 2.0 cm. The
effective area of the brake pads on each of...(Solved)
The master cylinder piston in a car braking system has a diameter of 2.0 cm. The
effective area of the brake pads on each of the four wheels is 30 cm2
. The driver
exerts a force of 500 n on the brake pedal. Calculate
a) The pressure in the master cylinder
b) The total braking force in the car.
Date posted: April 4, 2018. Answers (1)
- The area of the smaller piston of a hydraulic press is 0.01 m2 and that of the bigger piston is 0.5 m2. If the force...(Solved)
The area of the smaller piston of a hydraulic press is 0.01 m2
and that of the bigger
piston is 0.5 m. If the force applied to the smaller piston is 2 N, what force is
transmitted to the larger piston?
Date posted: April 4, 2018. Answers (1)
- Explain how a hydraulic press works(Solved)
Explain how a hydraulic press works
Date posted: April 4, 2018. Answers (1)
- Describe how a hydraulic brake system works(Solved)
Describe how a hydraulic brake system works
Date posted: April 4, 2018. Answers (1)
- Explain the applications of pressure in gases and liquids(Solved)
Explain the applications of pressure in gases and liquids
Date posted: April 4, 2018. Answers (1)
- The height of the mercury column in a barometer is found to be 67.0 cm at a certain place.
What would be the height of...(Solved)
The height of the mercury column in a barometer is found to be 67.0 cm at a certain place.
What would be the height of a water barometer at the same place? (densities of mercury-
1.36 × 104
kg/m3
and water- 1.0 × 103
kg/m3
).
Date posted: April 4, 2018. Answers (1)
- The density of mercury is 13,600 kgm-3
. Determine the liquid pressure at a point 76 cm
below the surface of mercury. (Take g = 10...(Solved)
The density of mercury is 13,600 kgm-3
. Determine the liquid pressure at a point 76 cm
below the surface of mercury. (Take g = 10 Nkg-1
)
S
Date posted: April 4, 2018. Answers (1)
- A diver is 10 m below the surface of water in a dam. If the density of water is 1,000 kgm-3
, determine the pressure due...(Solved)
A diver is 10 m below the surface of water in a dam. If the density of water is 1,000 kgm-3
, determine the pressure due to the water on the diver. (Take g = 10 Nkg-1
)
Date posted: April 4, 2018. Answers (1)
- A man of mass 84 kg stands upright on a floor. If the area of contact of his shoes and
the floor is 420 cm2
,...(Solved)
A man of mass 84 kg stands upright on a floor. If the area of contact of his shoes and
the floor is 420 cm2
, determine the average pressure he exerts on the floor. (Take g =
10 N/Kg)
Date posted: April 4, 2018. Answers (1)
- Differentiate between scalar and vector quantity giving examples(Solved)
Differentiate between scalar and vector quantity giving examples
Date posted: April 3, 2018. Answers (1)
- Explain the differences between mass and weight(Solved)
Explain the differences between mass and weight
Date posted: April 3, 2018. Answers (1)
-
An astronaut weighs 900 N on earth. On the moon he weighs 150 N. Calculate the moons’
gravitational strength. (Take g = 10 N/kg)(Solved)
An astronaut weighs 900 N on earth. On the moon he weighs 150 N. Calculate the moons’
gravitational strength. (Take g = 10 N/kg)
Date posted: April 3, 2018. Answers (1)
- What is induction? What is earthing?(Solved)
What is induction?
What is earthing?
Date posted: April 3, 2018. Answers (1)
- 100 cm3
of fresh water of density 1,000 kgm-3
is mixed with 100 cm3
of sea water of density
1030 kgm-3
. Calculate the density of the mixture(Solved)
100 cm3
of fresh water of density 1,000 kgm-3
is mixed with 100 cm3
of sea water of density
1030 kgm-3
. Calculate the density of the mixture
Date posted: April 3, 2018. Answers (1)
- The mass of an empty density bottle is 20 g. Its mass when filled with water is 40.0 g and
50.0 g when filled with...(Solved)
The mass of an empty density bottle is 20 g. Its mass when filled with water is 40.0 g and
50.0 g when filled with liquid X. Calculate the density of liquid X if the density of water is
1,000 kgm-3
.
Date posted: April 3, 2018. Answers (1)
- The relative density of some type of wood is 0.8. Find the density of the wood in kg/m3(Solved)
The relative density of some type of wood is 0.8. Find the density of the wood in kg/m3
Date posted: April 3, 2018. Answers (1)
- The density of concentrated sulphuric acid is 1.8 g/cm3
. Calculate the volume of 3.1
kg of the acid.(Solved)
The density of concentrated sulphuric acid is 1.8 g/cm3
. Calculate the volume of 3.1
kg of the acid.
Date posted: April 3, 2018. Answers (1)
- A block of glass of mass 187.5 g is 5.0 cm long, 2.0 cm thick and 7.5 cm high.
Calculate the density of the glass...(Solved)
A block of glass of mass 187.5 g is 5.0 cm long, 2.0 cm thick and 7.5 cm high.
Calculate the density of the glass in kgm-3
.
Date posted: April 3, 2018. Answers (1)