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Circle screw Rule- Pointed end of screw, direction of current
- Direction of rotation, direction of magnetic field lines.
OR
Right hand chip Rule- Thumb, direction of current
-Fingers points to direction of magnetic field.
Amperes swim rule -
Kavungya answered the question on October 3, 2019 at 06:26
- The figure below shows a transparent water tank containing water. An electric lamp surrounded by a shield with a narrow slit of fixed at corner...(Solved)
The figure below shows a transparent water tank containing water. An electric lamp surrounded by a shield with a narrow slit of fixed at corner A of the tank. A light ray from the slit shines on the water surface BC, at an angle of 48o as shown.
a)Determine the angle of refraction for the ray shown.
b)Complete the ray diagram to show the refracted ray.
c)Determine the angle of incidence for which the angle of refraction is 90o.
d)Calculate the speed of light in water.
Date posted: October 3, 2019. Answers (1)
- A ray of light is incident at an angle of 30o to the mirror positioned along the line M, a shown in figure below
By what...(Solved)
A ray of light is incident at an angle of 30o to the mirror positioned along the line M, a shown in figure below
By what angle should the mirror be rotated about 0 to the position M2 for the reflected ray to pass along M1
Date posted: October 3, 2019. Answers (1)
- A luminous point object took 3 seconds to move uniformly from P to Q in front a pin hole camera as shown in figure below
Determine...(Solved)
A luminous point object took 3 seconds to move uniformly from P to Q in front a pin hole camera as shown in figure below
Determine the speed of the image on the screen in cm/s
Date posted: October 3, 2019. Answers (1)
- Study the ray diagram in figure below. The observer should be able to see the reflected image after the mirror M2. Show the position of...(Solved)
Study the ray diagram in figure below. The observer should be able to see the reflected image after the mirror M2. Show the position of the image
Date posted: October 3, 2019. Answers (1)
- In figure below the current in the circuit is 1.80A
(i)Find the effective resistance between X and Y.
(ii)The p.d of the source.
(iii)Current through the 3? resistor (Solved)
In figure below the current in the circuit is 1.80A
(i)Find the effective resistance between X and Y.
(ii)The p.d of the source.
(iii)Current through the 3Ω resistor
Date posted: October 3, 2019. Answers (1)
- Explain why a 12V car battery is able to start the motor car engine while eight dry cells of 1.5 v each connected in series...(Solved)
Explain why a 12V car battery is able to start the motor car engine while eight dry cells of 1.5 v each connected in series will not.
Date posted: October 3, 2019. Answers (1)
- (a) An experiment was performed in the laboratory in the sequence described
I. Brought a positively charged plastic ruler near to the cap of an uncharged...(Solved)
(a) An experiment was performed in the laboratory in the sequence described
I. Brought a positively charged plastic ruler near to the cap of an uncharged leaf electroscope
II. Touched the cap momentarily with the finger
III. Removed the ruler
Draw diagram to show charge distribution on the cap and leaf of the electroscope and the position of the leaf after each of the above procedure.
(b) What will be the effect observed if the ruler is removed before removing the finger?
(c) In a separate experiment, the charged plastic ruler was allowed to touch the cap of electroscope. State giving a reason whether or not there will be any difference in the results obtained in (a) above
(d) In a nylon manufacturing factory heavy rubber units were put under the spinning machines which were made of metal to absorb the noise. The following effects were observed
A. Workers sometimes received electric shock when there was no leakage of charge from the main cable.
B. Small pieces of nylon stuck to the thread but whenever the room was moist this did not occur
(i) State and explain the reasons for the observation in A and B above.
(ii) How would the effect in (d) A be corrected
Date posted: October 3, 2019. Answers (1)
- Figure below shows two bar magnets placed with the north poles close together
Sketch the magnetic field pattern between the two north poles.(Solved)
Figure below shows two bar magnets placed with the north poles close together
Sketch the magnetic field pattern between the two north poles.
Date posted: October 3, 2019. Answers (1)
- A soldier standing 110m form a wall blows a whistle and hears an echo sometimes later. If the speed of sound in air is 33om/s,...(Solved)
A soldier standing 110m form a wall blows a whistle and hears an echo sometimes later. If the speed of sound in air is 33om/s, how long does it take the soldier to hear the echo of the whistle?
Date posted: October 3, 2019. Answers (1)
- Figure below shows a bulb connected across a 6v supply through a resistance wire XY of length 25m
Compare and explain the brightness of the bulb...(Solved)
Figure below shows a bulb connected across a 6v supply through a resistance wire XY of length 25m
Compare and explain the brightness of the bulb if the wire was replaced by one of same material and same diameter but 50cm long.
Date posted: October 3, 2019. Answers (1)
- Figure below shows a coil of insulated wire wound on a horse shoe soft iron core AB and connected to a power supplyName the polarity...(Solved)
Figure below shows a coil of insulated wire wound on a horse shoe soft iron core AB and connected to a power supply
Name the polarity at;
A
B
Date posted: October 3, 2019. Answers (1)
- An object is placed 20cm in front of a concave mirror of focal length 10cm and another identical object is place 20cm infront of a...(Solved)
An object is placed 20cm in front of a concave mirror of focal length 10cm and another identical object is place 20cm infront of a plane mirror
(i) Give one similarity of the image formed.
(ii) Give one difference between the image formed.
Date posted: October 3, 2019. Answers (1)
- In figure below power dissipated by the 16? resistor is 8w, what is the power dissipated in 200?(Solved)
In figure below power dissipated by the 16Ω resistor is 8w, what is the power dissipated in 200Ω
Date posted: October 3, 2019. Answers (1)
- 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)