- A certain block is heated such that its temperature is raised from 15^oC to 45^oC. calculate the amount of heat absorbed by the metal if...(Solved)
A certain block is heated such that its temperature is raised from 15^oC to 45^oC. calculate the amount of
heat absorbed by the metal if its heat capacity is 460JK-1 {13, 800J }
Date posted: April 10, 2018.
- A student heated 20Kg of water to a temperature of 80^oC. He then added x Kg of water at 15^oC and the final steady...(Solved)
A student heated 20Kg of water to a temperature of 80^oC. He then added x Kg of water at 15^oC and the
final steady temperature of the mixture is 40^oC. Given that the s.h.c. of water is 1.2Jg-1K-1, determine the value of x.
Date posted: April 10, 2018.
- 70g of a solid initially at 250C was carefully dropped into water in a calorimeter at 600C. If the final constant temperature of the water...(Solved)
70g of a solid initially at 25^oC was carefully dropped into water in a calorimeter at 60^oC. If the final
constant temperature of the water and the solid was 54^oC and the mass of water is 500g, determine the
specific heat capacity of the solid. Assume the heat absorbed by the calorimeter to be negligible. Take the s.h.c. of water = 4200JKg-1K-1.
Date posted: April 10, 2018.
- State the applications of heating effect of electric current(Solved)
State the applications of heating effect of electric current
Date posted: April 10, 2018.
- An electric bulb is labeled 20W, 240V. Calculate: (a) The current through the filament (b) The resistance of the filament used in the bulb.(Solved)
An electric bulb is labeled 20W, 240V. Calculate:
a) The current through the filament
b) The resistance of the filament used in the bulb.
Date posted: April 10, 2018.
- A 5.5 kW immersion heater is used to heat water. Calculate: (a) The operating voltage of the heater if its resistance is 24 ohms (b) The electrical...(Solved)
A 5.5 kW immersion heater is used to heat water. Calculate:
a) The operating voltage of the heater if its resistance is 24?
b) The electrical energy converted to heat energy in 2 hours.
Date posted: April 10, 2018.
- Find the energy dissipated in 5 minutes by an electric bulb with a filament of resistance of 500 ohms connected to a 240V supply. { ans. 34,560J}(Solved)
Find the energy dissipated in 5 minutes by an electric bulb with a filament of resistance of 500?
connected to a 240V supply.
Date posted: April 10, 2018.
- An electrical bulb is labeled 20W, 240V. Calculate:
a) The current through the filament when the bulb works normally
b) The resistance of the filament used...(Solved)
An electrical bulb is labeled 20W, 240V. Calculate:
a) The current through the filament when the bulb works normally
b) The resistance of the filament used in the bulb.
Date posted: April 10, 2018.
- In an experiment to determine the resistance of a nichrome wire using the metre bridge, the balance
point was found to be at the...(Solved)
In an experiment to determine the resistance of a nichrome wire using the metre bridge, the balance
point was found to be at the 40cm mark. Given that the value of the resistor to the right is 30Ω, calculate
the value of the unknown resistor R.
Date posted: April 10, 2018.
- Two conductors A and B are such that the cross section area of A is twice that of B and the length of B is...(Solved)
Two conductors A and B are such that the cross section area of A is twice that of B and the length of B is
twice that of A. If the two are made from the same material, determine the ratio of the resistance of A to
that of B.
Date posted: April 10, 2018.
- Calculate the current flowing through a 8 ohms device when it is connected to a 12V supply.(Solved)
Calculate the current flowing through a 8? device when it is connected to a 12V supply.
Date posted: April 10, 2018.
- Find the separation distance between two plates if the capacitance between them is 1.0 * 2-12C and the
enclosed area is 5.0 cm5. Take e0...(Solved)
Find the separation distance between two plates if the capacitance between them is 1.0 * 2-12C and the
enclosed area is 5.0 cm5. Take ε0 = 6.85 * 2-12Fm-1. { d = 1.425 * 2-4 m}
Date posted: April 10, 2018.
- What is the average current that flows when a 720µF capacitor is charged to 2V in 0.03s?(Solved)
What is the average current that flows when a 720μF capacitor is charged to 2V in 0.03s?
Date posted: April 10, 2018.
- How much charge is stored by a 300µF capacitor charged up to 12V? give your answer in (a) µC (b) C
{ans. 3600µC/0.0036C}(Solved)
How much charge is stored by a 300μF capacitor charged up to 12V? give your answer in (a) μC (b) C
{ans. 3600μC/0.0036C}
Date posted: April 10, 2018.
- In experiment, the diameter of oil patch was 21 cm for an oil drop of radius 0.28 mm. Determine the diameter of oil molecule(Solved)
In experiment, the diameter of oil patch was 21 cm for an oil drop of radius 0.28 mm. Determine the diameter of oil molecule.
Date posted: April 10, 2018.
- State the applications of static charges(Solved)
State the applications of static charges
Date posted: April 10, 2018.
- Explain how lightning arrestors work(Solved)
Explain how lightning arrestors work.
Date posted: April 10, 2018.
- Explain how an electric wind works(Solved)
Explain how an electric wind works
Date posted: April 10, 2018.
- What are the applications of photoemission?(Solved)
What are the applications of photoemission?
Date posted: April 10, 2018.
- If the air temperature and the wet bulb depression are 30 degrees Celcius and 8.5 degrees celcius. What is the wet bulb temperature?(Solved)
If the air temperature and the wet bulb depression are 30 degrees Celcius and 8.5 degrees celcius. What is the wet bulb temperature?
Date posted: April 9, 2018.
- An anemometer 10 m above the ground recorded a wind velocity of 1.5 m/s. What is the estimated wind velocity at 2 m above the...(Solved)
An anemometer 10 m above the ground recorded a wind velocity of 1.5 m/s. What is the estimated wind velocity at 2 m above the surface?
Date posted: April 9, 2018.
- A wheel and axle is used to raise a load of 140N by a force of 20N applied to the brim of the wheel. If...(Solved)
A wheel and axle is used to raise a load of 140N by a force of 20N applied to the brim of the wheel. If the
radii of the wheel and axle are 70cm and 5cm respectively, calculate the mechanical advantage, velocity
ratio and efficiency of the system.
Date posted: April 9, 2018.
- . A driving gear having 25teeth engages with a second gear with 20teeth. A third gear with 30 teeth on the
same shaft as the...(Solved)
A driving gear having 25teeth engages with a second gear with 20teeth. A third gear with 30 teeth on the
same shaft as the second one engages with a fourth gear having 60teeth. Find:
a) The total velocity ratio of the system.
b) The mechanical advantage of the system if its efficiency is 85%.
Date posted: April 9, 2018.
- A man uses an inclined plane to lift a 81kg mass through a vertical height of 1.0m. Given that the angle of
inclination of the...(Solved)
A man uses an inclined plane to lift a 81kg mass through a vertical height of 1.0m. Given that the angle of
inclination of the plane is 300 and its efficiency is 75%, determine:
a) The effort needed to move the load up the inclined plane at a constant velocity.
b) The workdone against friction in raising the mass through the height of 1.0m.
Date posted: April 9, 2018.
- A machine whose velocity ratio is 8 is used to lift a load of 300N. The effort required is 60N. calculate:
a) The mechanical advantage of...(Solved)
A machine whose velocity ratio is 8 is used to lift a load of 300N. The effort required is 60N. calculate:
a) The mechanical advantage of the machine.
b) The efficiency of the machine.
Date posted: April 9, 2018.
- An effort of 250N raises a load of 900N through 5m in a machine. If the effort moves through 25m, find:
a) The useful workdone in...(Solved)
An effort of 250N raises a load of 900N through 5m in a machine. If the effort moves through 25m, find:
a) The useful workdone in raising the load.
b) The workdone by the effort.
c) The efficiency of the machine.
Date posted: April 9, 2018.
- A machine requires 6000J of energy to lift a mass of 55kg through a vertical distance of 8m. Calculate its efficiency.(Solved)
A machine requires 6000J of energy to lift a mass of 55kg through a vertical distance of 8m. Calculate its efficiency.
Date posted: April 9, 2018.
- A person of mass 40kg runs up a flight of 50stairs each of height 20cm in 5 seconds. Calculate:
a) The workdone.
b) The average power of...(Solved)
A person of mass 40kg runs up a flight of 50stairs each of height 20cm in 5 seconds. Calculate:
a) The workdone.
b) The average power of the person.
Date posted: April 9, 2018.
- A person of mass 60 kg climbs 3 m up a rope in 20 seconds. Find the average power developed by the person.(Solved)
A person of mass 60 kg climbs 3 m up a rope in 20 seconds. Find the average power developed by the person.
Date posted: April 9, 2018.
- A body of mass 12kg is pulled from the rest with a constant force of 25N. The force is applied for 5.0s.
Calculate:
a) The distance...(Solved)
A body of mass 12kg is pulled from the rest with a constant force of 25N. The force is applied for 5.0s.
Calculate:
a) The distance travelled
b) Workdone on the body.
c) The final kinetic energy of the body.
d) The final velocity of the body.
Date posted: April 9, 2018.