Iron gate when touched conducts heat away from the hand while wood does not because it is a poor conductor of heat
Kavungya answered the question on October 17, 2019 at 09:58
- A bullet of mass 20g moving with a velocity of 30m/s penetrates a sand bag and it’s brought to rest in 0.05 seconds. Find the...(Solved)
A bullet of mass 20g moving with a velocity of 30m/s penetrates a sand bag and it’s brought to rest in 0.05 seconds. Find the average retarding force of the sand.
Date posted: October 17, 2019. Answers (1)
- A tightly fitted bottle cork will be easier to remove if the bottle is warmed. Explain this using kinetic and thermal property of matter.(Solved)
A tightly fitted bottle cork will be easier to remove if the bottle is warmed.
Explain this using kinetic and thermal property of matter.
Date posted: October 17, 2019. Answers (1)
- State one way of increasing sensitivity of mercury in glass thermometer.(Solved)
State one way of increasing sensitivity of mercury in glass thermometer.
Date posted: October 17, 2019. Answers (1)
- The figure below is that of identical springs. A 60N weight is attached on the springs as shown
so that the total extension for the...(Solved)
The figure below is that of identical springs. A 60N weight is attached on the springs as shown
so that the total extension for the system is 6cm. Calculate the spring constant of one spring.
Date posted: October 17, 2019. Answers (1)
- A mercury barometer reads 75cmHg at the base of Mt.Kenya. Assuming that the height of
the mountain is 1088m and the average density of air...(Solved)
A mercury barometer reads 75cmHg at the base of Mt.Kenya. Assuming that the height of
the mountain is 1088m and the average density of air is 1.25kg/m3. What is the reading of the
barometer at the top of the mountain? (Take density of mercury is 13.6g/cm3.)
Date posted: October 17, 2019. Answers (1)
- The figure below is that of a uniform meter rule supported at the 30cm. A load of 5N is attached at
the 0cm mark and...(Solved)
The figure below is that of a uniform meter rule supported at the 30cm. A load of 5N is attached at
the 0cm mark and that of 2N to a pulley at the 100cm mark. Calculate the weight of the meter rule.
Date posted: October 17, 2019. Answers (1)
- Before using a vernier calipers to measure diameter of a steel ball, a student confirmed that it had a zero error of -0.03cm. The figure...(Solved)
Before using a vernier calipers to measure diameter of a steel ball, a student confirmed that it had a zero error of -0.03cm. The figure below shows the vernier calipers scale when in use.
State the correct diameter of the steel ball.
Date posted: October 17, 2019. Answers (1)
- A conductor through which an electric current is flowing into the paper in a magnetic field as shown in figure below.
On the same diagram sketch...(Solved)
A conductor through which an electric current is flowing into the paper in a magnetic field as shown in figure below.
On the same diagram sketch the resulting magnetic field pattern and show the direction of the resulting mechanical force F, on the conductor.
Date posted: October 3, 2019. Answers (1)
- Figure below shows a solenoid with a ferromagnetic core connected to a battery E, ammeter A and rheostat R
On the figure indicate;
(i)The direction of current...(Solved)
Figure below shows a solenoid with a ferromagnetic core connected to a battery E, ammeter A and rheostat R
On the figure indicate;
(i)The direction of current in the external circuit and around the coils.
(ii)The polarity of the resulting electromagnet
(iii)The direction of the magnetic field lines created around the solenoid
Date posted: October 3, 2019. Answers (1)
- State and explain a rule you would apply to determine the direction of the magnetic flux round a conductor carrying an electric current.(Solved)
State and explain a rule you would apply to determine the direction of the magnetic flux round a conductor carrying an electric current.
Date posted: October 3, 2019. Answers (1)
- 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)