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- In an experiment to determine the half-life of the radioactive element,the following data was obtained.(Solved)
In an experiment to determine the half-life of the radioactive element,the following data was obtained.
(i) Plot a decay curve for the element
(ii) Estimate from your graph the half-life of the element
Date posted: October 2, 2019. Answers (1)
- Use a suitable equation to show this decay(Solved)
Radon nuclide 
decays to form polonium by emitting an alpha- particle use a suitable equation to show this decay
Date posted: October 2, 2019. Answers (1)
- Define background count(Solved)
Define background count
Date posted: October 2, 2019. Answers (1)
- The diagram below represents an X –ray tube. The anode is made up of copper metal and tungsten as the target.(Solved)
The diagram below represents an X –ray tube. The anode is made up of copper metal and tungsten as the target.
a) What are the functions of parts A and B.
b) Explain how X-rays are produced from the tube
c) Why is tungsten used for the target in the tube?
d) How can the quality of X-rays produced be controlled in the tube?
e) How can the quantity of the X-rays be increased?
Date posted: October 2, 2019. Answers (1)
- Determine the amount of current passing through the 2O resistor shown in the figure below(Solved)
Determine the amount of current passing through the 2Ω resistor shown in the figure below
Date posted: October 2, 2019. Answers (1)
- The figure below shows two ways of biasing a P-N junction(Solved)
The figure below shows two ways of biasing a P-N junction
(i) In which circuit will current flow?
(ii) Explain your answer in (i) above.
Date posted: October 2, 2019. Answers (1)
- The energy of a radiation is 3.8 x10-14 J.(Solved)
The energy of a radiation is 3.8 x10-14 J. Determine the wavelength of the radiation
( h = 6.63x10-34JS,C=3.0 x 108m/s)
Date posted: October 2, 2019. Answers (1)
- Arrange the following radiations in order of increasing wavelength(Solved)
Arrange the following radiations in order of increasing wavelength; Ultra-violet, Microwaves, Blue light, Yellow light
Date posted: October 2, 2019. Answers (1)
- Figure below shows an object at the bottom of a water container. Draw rays on the diagram to show the object as viewed from above. (Solved)
Figure below shows an object at the bottom of a water container. Draw rays on the diagram to show the object as viewed from above.
Date posted: October 1, 2019. Answers (1)
- A girl looks into a plane mirror 3 m in front of her and sees the image of the wall which is 2.5 m behind her. What...(Solved)
A girl looks into a plane mirror 3 m in front of her and sees the image of the wall which is 2.5 m behind her. What is the difference between the girl’s eyes and the image of the wall?
Date posted: October 1, 2019. Answers (1)
- It is observed that when a magnet breaks up into two, each of the pieces retains the characteristics of the original magnet. Explain(Solved)
It is observed that when a magnet breaks up into two, each of the pieces retains the characteristics of the original magnet. Explain
Date posted: October 1, 2019. Answers (1)
- The figure below shows a bimetallic strip made of copper and iron at room temperature
If copper expands more than iron. Identify A and B if...(Solved)
The figure below shows a bimetallic strip made of copper and iron at room temperature
If copper expands more than iron. Identify A and B if the bimetallic strip is placed in a refrigerator whose temperature is -700c.
Date posted: October 1, 2019. Answers (1)
- The figure below shows how volume of a given mass of water varies with temperature.
sketch a graph of density against Temperature.(Solved)
The figure below shows how volume of a given mass of water varies with temperature.
sketch a graph of density against Temperature.
Date posted: October 1, 2019. Answers (1)
- The following results were obtained in a experiment to verify Hooke’s law when a spring was extended by hanging various loads on it.
(I) Complete...(Solved)
The following results were obtained in a experiment to verify Hooke’s law when a spring was extended by hanging various loads on it.
(I) Complete the table for the extension e above.
(II) Plot a graph of load (y-axis) against extension
(III) From the graph determine the springs constant
(IV) Calculate the energy stored when the spring is stretched to 16 cm.
Date posted: October 1, 2019. Answers (1)
- A stone of mass 5g is released from a catapult. The catapult is stretched by 10cm. If the constant of elasticity is 100N/cm. Calculate;
(i)...(Solved)
A stone of mass 5g is released from a catapult. The catapult is stretched by 10cm. If the constant of elasticity is 100N/cm. Calculate;
(i) The horizontal velocity with which the stone is released
(ii) Sketch a graph of horizontal velocity against time from the time the stone is released to when it reaches the ground.
Date posted: October 1, 2019. Answers (1)
- The figure below shows the variation force with extension for a steel coil spring.
(i) On the same axes, sketch the variation of force with extension...(Solved)
The figure below shows the variation force with extension for a steel coil spring.
(i) On the same axes, sketch the variation of force with extension for a wire form which the spring is made.
(ii) Explain the difference between the two lines drawn
Date posted: October 1, 2019. Answers (1)
- The figure below shows a section of a tape from a ten tick timer whose frequency is 50 Hz.
Calculate;
(i) The average velocity of the...(Solved)
The figure below shows a section of a tape from a ten tick timer whose frequency is 50 Hz.
Calculate;
(i) The average velocity of the trolley between points
1. WX
2. YZ
(ii) Find the acceleration of the trolley.
Date posted: October 1, 2019. Answers (1)
- The velocity time graph in the figure below illustrates the motion of a ball which has been projected vertically upwards from the surface of...(Solved)
The velocity time graph in the figure below illustrates the motion of a ball which has been projected vertically upwards from the surface of a planet. The weight of the ball on earth is 30N
Determine the weight of a ball on the planet
Date posted: October 1, 2019. Answers (1)
- A modern car has a strengthened passenger cage but with front and back regions which can collapse in a crash. Explain how this collapsible...(Solved)
A modern car has a strengthened passenger cage but with front and back regions which can collapse in a crash. Explain how this collapsible regions should reduce injury in a car crash.
Date posted: October 1, 2019. Answers (1)
- State one way of making surface tension of water stronger.(Solved)
State one way of making surface tension of water stronger.
Date posted: October 1, 2019. Answers (1)