- The initial mass of a radioactive substance is 20g. The substance has a half -life of 5 years. Determine the mass remaining after 20 years.(Solved)
The initial mass of a radioactive substance is 20g. The substance has a half -life of 5 years. Determine the mass remaining after 20 years.
Date posted: May 31, 2019. Answers (1)
- The diagram below shows an arrangement of capacitors in a circuit.
Determine:-
(i) The total capacitance
(ii) The total charge
(iii) The energy stored by the 2µF...(Solved)
The diagram below shows an arrangement of capacitors in a circuit.
Determine:-
(i) The total capacitance
(ii) The total charge
(iii) The energy stored by the 2μF capacitor.
Date posted: May 31, 2019. Answers (1)
- Explain why carbon -14 is radioactive while Carbon -12 is not.(Solved)
Explain why carbon -14 is radioactive while Carbon -12 is not.
Date posted: May 31, 2019. Answers (1)
- The cell in the figure below has an e.m.f. of 1.8V and negligible internal resistance.
Determine:-
(i) Total resistance in the circuit.
(ii) The current in the...(Solved)
The cell in the figure below has an e.m.f. of 1.8V and negligible internal resistance.
Determine:-
(i) Total resistance in the circuit.
(ii) The current in the circuit.
(iii) Reading of the voltmeter.
Date posted: May 31, 2019. Answers (1)
- The figure below shows an object O infront of a concave mirror and its image, I, formed after reflection.
On the same diagram draw appropriate ray(s)...(Solved)
The figure below shows an object O infront of a concave mirror and its image, I, formed after reflection.
On the same diagram draw appropriate ray(s) to locate the principal focus F, of the mirror.
Date posted: May 31, 2019. Answers (1)
- The figure below shows a ray of light incident in the face of a water prism.
Sketch the path of the ray of light as it...(Solved)
The figure below shows a ray of light incident in the face of a water prism.
Sketch the path of the ray of light as it passes through the prism. Critical angle for water is 49°.
Date posted: May 31, 2019. Answers (1)
- In figure shown below (not drawn to scale), sketch the path of a ray till it emerges from the prism.(Solved)
In figure shown below (not drawn to scale), sketch the path of a ray till it emerges from the prism.
Date posted: May 31, 2019. Answers (1)
- The figure below shows a series of wave fronts one wavelength apart approaching a gap between barriers in ripple tank.
On the same diagram, show what...(Solved)
The figure below shows a series of wave fronts one wavelength apart approaching a gap between barriers in ripple tank.
On the same diagram, show what happens when the waves pass through the gap.
Date posted: May 31, 2019. Answers (1)
- The figure below shows wave fronts approaching a concave sphere.
Complete the diagram to show wave fronts formed after striking the surface. Show how focal point...(Solved)
The figure below shows wave fronts approaching a concave sphere.
Complete the diagram to show wave fronts formed after striking the surface. Show how focal point of the surface is located.
Date posted: May 31, 2019. Answers (1)
- The figure below shows a displacement time graph for a wave motion.
What is the frequency of the wave?(Solved)
The figure below shows a displacement time graph for a wave motion.
What is the frequency of the wave?
Date posted: May 31, 2019. Answers (1)
- The figure below shows a diagram of a current -carrying wire wound on a U-shaped soft iron.
Draw the magnetic field pattern around P and Q.(Solved)
The figure below shows a diagram of a current -carrying wire wound on a U-shaped soft iron.
Draw the magnetic field pattern around P and Q.
Date posted: May 31, 2019. Answers (1)
- The plates of a simple cell are connected through a torch bulb and then dipped into dilute sulphuric acid on a beaker. The
bulb lights brightly...(Solved)
The plates of a simple cell are connected through a torch bulb and then dipped into dilute sulphuric acid on a beaker. The
bulb lights brightly for a short time. State two possible causes of this.
Date posted: May 31, 2019. Answers (1)
- The coil of an electric motor is usually wound on a soft iron armature. State two purposes of this armature.(Solved)
The coil of an electric motor is usually wound on a soft iron armature. State two purposes of this armature.
Date posted: May 31, 2019. Answers (1)
- A boy observes his face in a concave mirror of focal length 100cm. If the mirror is 80cm away, state one characteristic of the image...(Solved)
A boy observes his face in a concave mirror of focal length 100cm. If the mirror is 80cm away, state one characteristic of the image observed.
Date posted: May 31, 2019. Answers (1)
- The figure below shows the image behind a mirror M.
By ray diagram construction, locate the position of the object.(Solved)
The figure below shows the image behind a mirror M.
By ray diagram construction, locate the position of the object.
Date posted: May 31, 2019. Answers (1)
- Explain why a body moving in horizontal circular motion does no work.(Solved)
Explain why a body moving in horizontal circular motion does no work.
Date posted: May 31, 2019. Answers (1)
- A transformer has 800 turn in the primary and 40 turns in the secondary winding. The alternating
e.m.f connected to the primary is 240v and the...(Solved)
A transformer has 800 turn in the primary and 40 turns in the secondary winding. The alternating
e.m.f connected to the primary is 240v and the current is 0.5A.
Determine
i) The secondary e.m.f
ii) The power in the secondary if the transformer is 95% efficient.
Date posted: May 31, 2019. Answers (1)
- A bar magnet is moved into a coil of insulated copper wire connected to a centre-zero galvanometer as shown in figure below.
i) Show on the...(Solved)
A bar magnet is moved into a coil of insulated copper wire connected to a centre-zero galvanometer as shown in figure below.
i) Show on the diagram the direction of induced current in the coil.
ii) State and explain clearly what is observed on the galvanometer when the magnet is moved into and then withdrawn from the coil.
Date posted: May 31, 2019. Answers (1)
- A pendulum bob is raised to a height of 60cm above its lowest point and made to swing as shown in the figure.
Determine the velocity...(Solved)
A pendulum bob is raised to a height of 60cm above its lowest point and made to swing as shown in the figure.
Determine the velocity of the mass at the height where kinetic energy is equal to the potential energy.
Date posted: May 31, 2019. Answers (1)
- Figure below shows two rays of monochromatic light incident on two adjacent slits S1 and S2
State what is observed on the screen when the:
i) Distance...(Solved)
Figure below shows two rays of monochromatic light incident on two adjacent slits S1 and S2
State what is observed on the screen when the:
i) Distance X is increased.
ii) Slit separation, d is reduced.
iii) White light is used.
Date posted: May 31, 2019. Answers (1)