Heat gained by calorimeter
= 60 x 10-3 x 378 ( 45 – 25) J;
= 453.6 J
Heat gained by water
= 100 x 10-3 x 4.200 ( 45 – 25J;
= 8.400J
Heat lost by condensing steam = m/
( 163.5 – 160 ) x 10^-3/J
= 3.5 x 10^-3 x / J
Heat lost 3.5 g of ( condensed steam) water cooling to 45^0C
3.5 x 10^-3 ( 100 – 45) x 4,200;
= 808.5J
Heat given = heat gained
Hence:
3.5 / x 10^-3 + 808.5 J = 453 6J + 8,400J;
= 2.3 x 10^-6 J/Kg;
Githiari answered the question on September 19, 2017 at 07:09
- A body moving initially at 50m/s decelerates uniformly at 2ms-2 until it comes to rest.
What distance does it cover from the time it started...(Solved)
A body moving initially at 50m/s decelerates uniformly at 2ms-2 until it comes to rest.
What distance does it cover from the time it started to decelerate
Date posted: September 19, 2017. Answers (1)
- A accelerates uniformly from it initial velocity, u, the final velocity, v in time t. The distance
traveled during this time is S. If the acceleration...(Solved)
A accelerates uniformly from it initial velocity, u, the final velocity, v in time t. The distance
traveled during this time is S. If the acceleration is denoted by the letter, a show that;
(i) V = u + at
(ii) S = ut + at2
(iii) V2 = u2 + as
Date posted: September 19, 2017. Answers (1)
- An observer A is in a moving vehicle with a siren on while an observer B is stationary on the side
of the road. State the...(Solved)
An observer A is in a moving vehicle with a siren on while an observer B is stationary on the side
of the road. State the difference between the sound heard by A and B as the vehicle approaches B
at a high constant speed
Date posted: September 18, 2017. Answers (1)
- In some petrol engines where spark plugs are used, a capacitor is connected to the distributor.
Suggest the function of the capacitor.(Solved)
In some petrol engines where spark plugs are used, a capacitor is connected to the distributor.
Suggest the function of the capacitor.
Date posted: September 18, 2017. Answers (1)
- Equal masses of water and paraffin with specific heat capacities CW and CP respectively are heated
using identical sources of heat, for the same length of...(Solved)
Equal masses of water and paraffin with specific heat capacities CW and CP respectively are heated
using identical sources of heat, for the same length of time. The final temperature θP of paraffin
was found to be greater than final temperature than of water, Show that CW is greater than CP.
Date posted: September 18, 2017. Answers (1)
- A girl heats 5 kg of water to temperature of 80oC. When she adds m kg of water at 15oC the mixture attains...(Solved)
A girl heats 5 kg of water to temperature of 80oooC. Determine the value of m. (ignore heat changes due to the container)
Date posted: September 18, 2017. Answers (1)
- What characteristics of sound is applied in turning pianos(Solved)
What characteristics of sound is applied in turning pianos
Date posted: September 18, 2017. Answers (1)
- What measurable quality is associated with colors of light?(Solved)
What measurable quality is associated with colors of light?
Date posted: September 18, 2017. Answers (1)
- Distinguish between PNP and NPN transistors(Solved)
Distinguish between PNP and NPN transistors
Date posted: September 18, 2017. Answers (1)
- State the condition for a minim to occur in an interference pattern(Solved)
State the condition for a minim to occur in an interference pattern
Date posted: September 18, 2017. Answers (1)
- Describe how a young’s double slit may be made in a laboratory(Solved)
Describe how a young’s double slit may be made in a laboratory
Date posted: September 18, 2017. Answers (1)
- A transformer of 480 turns in the primary coil is used to connect a 9 volt a.c electric device to a
240 v.a.c mains power supply....(Solved)
A transformer of 480 turns in the primary coil is used to connect a 9 volt a.c electric device to a
240 v.a.c mains power supply. Calculate the number of turns in the secondary coil.
Date posted: September 18, 2017. Answers (1)
- A researcher studying the behaviour of step- up transformer made the following
observations:
“More joules per coulomb and fewer coulombs per second at the output than at...(Solved)
A researcher studying the behaviour of step- up transformer made the following
observations:
“More joules per coulomb and fewer coulombs per second at the output than at the input terminals
Explain why the observation does not imply a violation of the principle of conservation of energy
Date posted: September 18, 2017. Answers (1)
- Define amplitude(Solved)
Define amplitude.
Date posted: September 18, 2017. Answers (1)
- State why optical fibres are preferred in communication to ordinary cables.(Solved)
State why optical fibres are preferred in communication to ordinary cables.
Date posted: September 18, 2017. Answers (1)
- State two defects of a simple cell and how each can be minimized(Solved)
State two defects of a simple cell and how each can be minimized.
Date posted: September 18, 2017. Answers (1)
- Give a reason why repulsion in magnetism is the surest way of testing polarity(Solved)
Give a reason why repulsion in magnetism is the surest way of testing polarity
Date posted: September 18, 2017. Answers (1)
- An electron in an excited atom falls from energy levels E2 to energy level E1. Write an equation
relating the energy change to the frequency f,...(Solved)
An electron in an excited atom falls from energy levels E2 to energy level E1. Write an equation
relating the energy change to the frequency f, of the radiation emitted. Explain why new symbols
used.
Date posted: September 18, 2017. Answers (1)
- Define the term acceleration.(Solved)
Define the term acceleration.
Date posted: September 18, 2017. Answers (1)
- State two factors that would raise the boiling point of water to above 100oC.(Solved)
State two factors that would raise the boiling point of water to above 100oC.
Date posted: September 18, 2017. Answers (1)