- A 200g mass of copper was heated to 100°C and then transferred to a lagged copper calorimeter of mass 5g containing 125g of water at...(Solved)
A 200g mass of copper was heated to 100°C and then transferred to a lagged copper calorimeter of mass 5g containing 125g of water at 30°C. Calculate the final temperature of water. (Specific heat capacity of copper = 400J/KgK, water =4200J/KgK).
Date posted: May 31, 2019. Answers (1)
- Figure below shows an object placed 5cm in front of a convex lens whose focus length is 10cm.
a) On the same figure, draw a ray...(Solved)
Figure below shows an object placed 5cm in front of a convex lens whose focus length is 10cm.
a) On the same figure, draw a ray diagram to show the position of the image formed.
b) Use the ray diagram to determine
i) The image distance
ii) The image size
iii) The magnification
Date posted: May 31, 2019. Answers (1)
- The graph below shows how temperature of a 40kg of a substance varied with time as it was heated steadily by electrical
means. The heating coil...(Solved)
The graph below shows how temperature of a 40kg of a substance varied with time as it was heated steadily by electrical
means. The heating coil carried a current of 16A at a potential difference of 22V.
i) What is happening to the substance at AB?
ii) Determine the specific heat capacity of the substance in solid state.
Date posted: May 31, 2019. Answers (1)
- The figure (a) below shows a distance -time graph of a motion of a body.In the figure (b), sketch the corresponding velocity-time graph for the...(Solved)
The figure (a) below shows a distance -time graph of a motion of a body.In the figure (b), sketch the corresponding velocity-time graph for the same motion.
Date posted: May 31, 2019. Answers (1)
- The figure below shows a block diagram of a p-n junction diode.
On the same diagram, show how a cell may be connected so that it...(Solved)
The figure below shows a block diagram of a p-n junction diode.
On the same diagram, show how a cell may be connected so that it is reverse biased.
Date posted: May 31, 2019. Answers (1)
- A bullet is fired from a gun at a velocity of 10m/s. It strikes the tree, perpendicularly and penetrates deeply. If it stops just
as it...(Solved)
A bullet is fired from a gun at a velocity of 10m/s. It strikes the tree, perpendicularly and penetrates deeply. If it stops just
as it emerges through the other side of the tree,
i) Calculate the average retardation if the tree is 2m thick.
ii) Time taken by the bullet in the tree.
Date posted: May 31, 2019. Answers (1)
- The expression below is an equation for a radioactive element P. Element Q and R are the daughter nuclides. P, Q and R are not...(Solved)
The expression below is an equation for a radioactive element P. Element Q and R are the daughter nuclides. P, Q and R are not the actual symbols of any of the elements.
Identify the element R and state two of its characteristics.
Date posted: May 31, 2019. Answers (1)
- A ball is thrown vertically upwards from the ground. It rises up to the highest point and then returns to the ground.Taking
the upward velocity to...(Solved)
A ball is thrown vertically upwards from the ground. It rises up to the highest point and then returns to the ground.Taking
the upward velocity to be positive, sketch the velocity -time graph for the motion.
Date posted: May 31, 2019. Answers (1)
- The mass of the fabric of a large balloon is 100kg. The balloon is inflated with 200cm3 of helium. The balloon is attached to a...(Solved)
The mass of the fabric of a large balloon is 100kg. The balloon is inflated with 200cm3 of helium. The balloon is attached to a cable fixed to the ground as shown.
(Density of air and helium are 1.25kg/m3 and 0.2kg/m3 respectively)
i) Indicate all the forces acting on the system.
ii) If the system is at equilibrium, write an equation relating the three forces in (i) above.
iii) Calculate the upthrust on the balloon.
Date posted: May 31, 2019. Answers (1)
- Explain why most of the x-ray tube is surrounded by lead metal.(Solved)
Explain why most of the x-ray tube is surrounded by lead metal.
Date posted: May 31, 2019. Answers (1)
- Figure below shows circular waves approaching a plane barrier in uniform medium.
On the diagram sketch the reflected waves.(Solved)
Figure below shows circular waves approaching a plane barrier in uniform medium.
On the diagram sketch the reflected waves.
Date posted: May 31, 2019. Answers (1)
- A house has two 100w bulbs, two 60w bulbs and one 75w bulb. Determine the cost of having all the bulbs switched on for 60...(Solved)
A house has two 100w bulbs, two 60w bulbs and one 75w bulb. Determine the cost of having all the bulbs switched on for 60 hours, given that the cost of electricity is 50cents per kilowatt hour find the cost.
Date posted: May 31, 2019. Answers (1)
- Figure below shows an object placed in front of a convex mirror.
On the same diagram draw the appropriate rays and locate the image formed.(Solved)
Figure below shows an object placed in front of a convex mirror.
On the same diagram draw the appropriate rays and locate the image formed.
Date posted: May 31, 2019. Answers (1)
- Explain why objects float higher in salty water than in fresh water.(Solved)
Explain why objects float higher in salty water than in fresh water.
Date posted: May 31, 2019. Answers (1)
- A person of mass 50kg is on a swing which has a speed of 10m/s at the lowest point of its motion. The ropes of...(Solved)
A person of mass 50kg is on a swing which has a speed of 10m/s at the lowest point of its motion. The ropes of the swing
are 2.5m long, Find the tension of the ropes. (Take g = 10ms-2)
Date posted: May 31, 2019. Answers (1)
- A motorcycle is travelling at a constant speed of 72km/h around a circular track of radius 150m.
i) Determine its centripetal acceleration.
ii) How long does...(Solved)
A motorcycle is travelling at a constant speed of 72km/h around a circular track of radius 150m.
i) Determine its centripetal acceleration.
ii) How long does the cyclist take to complete one full cycle of the track?
Date posted: May 31, 2019. Answers (1)
- Figure below shows an incident ray normal to the surface BC of a right-angled glass prism ABC. The critical angle of the glass is 420
Complete...(Solved)
Figure below shows an incident ray normal to the surface BC of a right-angled glass prism ABC. The critical angle of the glass is 420
Complete the diagram to show the path of the ray.
Date posted: May 31, 2019. Answers (1)
- A current carrying conductor AB is in a magnetic field as shown in figure below.
a) Indicate the direction of the force F acting on the...(Solved)
A current carrying conductor AB is in a magnetic field as shown in figure below.
a) Indicate the direction of the force F acting on the conductor.
b) State two factors that determine the direction of the force F.
Date posted: May 31, 2019. Answers (1)
- State two factors on which the linear speed of a body moving in a circular motion depends.(Solved)
State two factors on which the linear speed of a body moving in a circular motion depends.
Date posted: May 31, 2019. Answers (1)
- A battery is rated 100AH. How long will it work if it steadily supplies a current of 2.5A(Solved)
A battery is rated 100AH. How long will it work if it steadily supplies a current of 2.5A
Date posted: May 31, 2019. Answers (1)