Get premium membership and access questions with answers, video lessons as well as revision papers.
- The stem is thin. This makes the hydrometer sensitive such that a small change in density of
liquid causes a large change on the stem.
- The bulb is large to make it float.
The bulb is heavy to make it float a upright.
Kavungya answered the question on April 5, 2019 at 05:22
- The figure below shows a balloon carrying hydrogen gas 3m3 of density 0.09kgm-3. The mass
of the balloon fabric is 2kg and the density of air...(Solved)
The figure below shows a balloon carrying hydrogen gas 3m3 of density 0.09kgm-3. The mass
of the balloon fabric is 2kg and the density of air is 1.25kgm-3
i) Determine the tension in the string
ii) If the string is suddenly cut, calculate the acceleration of the balloon upwards
iii) What is the maximum mass of the equipment the balloon can lift at a constant velocity
Date posted: April 5, 2019. Answers (1)
- A measuring cylinder contains 50cm3 of light oil at 0oC. When a lump of dried ice is placed in
the oil, the total volume is 72cm3....(Solved)
A measuring cylinder contains 50cm3 of light oil at 0oC. When a lump of dried ice is placed in
the oil, the total volume is 72cm3. Determine the density of the ice.
Date posted: April 5, 2019. Answers (1)
- A piece of metal N of mass 2kg weighs 18N in water and 12N in liquid M. Determine the density
of ;
(i) The metal N
(ii) The...(Solved)
A piece of metal N of mass 2kg weighs 18N in water and 12N in liquid M. Determine the density
of ;
(i) The metal N
(ii) The liquid M
Date posted: April 5, 2019. Answers (1)
- A bathroom shower has 200 holes each 2.5mm2 in area. Water flows from a pipe of cross-section
area of 15cm2 at 5m/s to the shower. Determine...(Solved)
A bathroom shower has 200 holes each 2.5mm2 in area. Water flows from a pipe of cross-section
area of 15cm2 at 5m/s to the shower. Determine the speed of the spray.
Date posted: April 5, 2019. Answers (1)
- A ship of mass 1300 tonnes floats on sea water:
(i) What volume of sea water is displaced (Density of sea water is 1025kg/m3)
(ii) Suppose it...(Solved)
A ship of mass 1300 tonnes floats on sea water:
(i) What volume of sea water is displaced (Density of sea water is 1025kg/m3)
(ii) Suppose it sails from sea water to fresh water, what cargo must be removed so that
the same volume of water is displaced? (Density of fresh water = 1000kg/m3
Date posted: April 5, 2019. Answers (1)
- The figure below shows how rays from a distant and near objects are focused inside a human
eye with a certain defect(Solved)
The figure below shows how rays from a distant and near objects are focused inside a human
eye with a certain defect
Name the defect and state the cause of the defect
Date posted: April 4, 2019. Answers (1)
- Sound tends to travel over longer distance at night. Explain(Solved)
Sound tends to travel over longer distance at night. Explain
Date posted: April 4, 2019. Answers (1)
- A boy standing in front of a cliff blows a whistle and hears the echo after 0.5 seconds. He then
moves 17m further away form the...(Solved)
A boy standing in front of a cliff blows a whistle and hears the echo after 0.5 seconds. He then
moves 17m further away form the cliff and blows the whistle again. He now hears the echo after
0.6seconds. Determine the speed of the sound
Date posted: April 4, 2019. Answers (1)
- A girl standing 220m from the foot of a high wall claps her hands and the echo reaches her
1.29 seconds later. Calculate the velocity of...(Solved)
A girl standing 220m from the foot of a high wall claps her hands and the echo reaches her
1.29 seconds later. Calculate the velocity of sound in air using this observation
Date posted: April 4, 2019. Answers (1)
- The human ear can distinguish two sounds as separate only if they need it at least 0.1 seconds
apart. How far from a wall must an...(Solved)
The human ear can distinguish two sounds as separate only if they need it at least 0.1 seconds
apart. How far from a wall must an observer be in order to hear an echo when he shouts.
(Speed of sound = 330m/s)
Date posted: April 4, 2019. Answers (1)
- Figure below shows a ray of light traveling from glass to water.(Solved)
Figure below shows a ray of light traveling from glass to water.
Calculate the angle of incidence if the refractive index of glass and water are 3/2 and 4/3 respectively
Date posted: April 4, 2019. Answers (1)
- The figure below represents a ray of light falling normally on the curved surface of a
semi- circular glass block A at an angle of 32°...(Solved)
The figure below represents a ray of light falling normally on the curved surface of a
semi- circular glass block A at an angle of 32° at O and emerging into air at an angle of 48°
Calculate the absolute refractive index of the glass of which the block is made.
(Assume air is a vacuum)
Date posted: April 4, 2019. Answers (1)
- The refractive index of paraffin is 1.47 and that of glass is 1.55. Determine the critical
angle of a ray of light travelling from glass to...(Solved)
The refractive index of paraffin is 1.47 and that of glass is 1.55. Determine the critical
angle of a ray of light travelling from glass to paraffin
Date posted: April 4, 2019. Answers (1)
- The following figure shows an electric circuit in which five resistors are connected
to a battery of e.m.f 4.0V and negligible internal resistance.(Solved)
The following figure shows an electric circuit in which five resistors are connected
to a battery of e.m.f 4.0V and negligible internal resistance.
Determine:
(i) The total resistance of the circuit
(ii) The potential difference between Y and Q
Date posted: April 4, 2019. Answers (1)
- In the circuit diagram below, X is a fixed resistor while Y can be varied between O
and 100ohms using a sliding jockey(Solved)
In the circuit diagram below, X is a fixed resistor while Y can be varied between O
and 100ohms using a sliding jockey
Calculate:
(i) The minimum possible current in the circuit
(ii) The maximum possible current in the circuit
Date posted: April 4, 2019. Answers (1)
- Four capacitors of capacitance, 3µf, 4µf, 5µf and 3µf are arranged as shown below. Find the total capacitance.(Solved)
Four capacitors of capacitance, 3μf, 4μf, 5μf and 3μf are arranged as shown below. Find the capacitance.
Date posted: April 4, 2019. Answers (1)
- In an experiment to determine the resistance of a nichrome wire using the metre bridge, the
balance point was found to be at 38cm mark. If...(Solved)
In an experiment to determine the resistance of a nichrome wire using the metre bridge, the
balance point was found to be at 38cm mark. If the value of the resistance in the right hand
gap needed to balance the bridge was 25ohms, Calculate the value of resistance of nichrome wire
Date posted: April 4, 2019. Answers (1)
- The diagram in the figure below shows a wheat stone bridge(Solved)
The diagram in the figure below shows a wheat stone bridge
K, L, M and N are four resistors joined as shown. The value of resistance of resistor K is
unknown. I1, I2, I3 and I4 are the amount of current passing through K, M, L and N respectively.
It is also provided that L is a variable resistor.
(i) Explain how the set-up is used to determine the value of unknown resistance of K
(ii) State why wheat stone bridge is more accurate in measuring resistance than the voltmeter-ammeter
method
Date posted: April 4, 2019. Answers (1)
- A transformer is designated to work from a 240V a.c. mains and to give a supply of 8V
to ring house bells. The primary has 4800...(Solved)
A transformer is designated to work from a 240V a.c. mains and to give a supply of 8V
to ring house bells. The primary has 4800 turns.
(i) What type of transformer is this? Give a reason.
(ii) Why is the iron core laminated?
(iii) Calculate the secondary turns if the efficiency is 100%.
Date posted: April 4, 2019. Answers (1)
- Study the circuit diagram shown below.(Solved)
Study the circuit diagram shown below.
(i) Determine the reading of the voltmeter V.
(ii) Determine the reading of the ammeter A.
(iii) Explain the effect on the reading of the voltmeter if the 3ohms resistor is altered to be 6ohms
Date posted: April 4, 2019. Answers (1)