Free KCSE Physics Topical Questions KNEC Standards

K.C.S.E Physics Q & A - MODEL 1996PP2QN07

5/7/2020

K.C.S.E Physics Q & A - MODEL 1996PP2QN07

(a) Describe with the aid of a diagram an experiment set up for observing photoelectric effect
(b) Table 2 shows the relationship between the wavelength, of a radiation falling on the surface and the energy, k of the emitted electrons

(i) Plot a graph of energy k ( y – axis) against the frequency, f, of the incident light
(ii) Determine the work function Φ of the surface used

(Speed of light, c = 3.00 * 108 ms^-1 planks constant h = 6.663 * 10^-34JS)

answers

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP2QN06

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP2QN06

(a) The fig. 4 shows the diagram of set up to investigate the variation of centripetal with the radius r, of the circle in which a body rotated

Describe how the set up can be used to carry out the investigation

Table 1 shows results obtained from an investigation similar to the one in part (a)
(i) Plot a graph of force, F ( y- axis) on the body against the radius , r, ( in meters)
(ii) Given that the mass of the body is 100g, use the graph to determine the angular velocity,

K.N.E.C ANSWERS

(a) Keep angular velocity Wl constant;
Centripetal force provided by mg;
Fix the mass m and measure of m;
Repeat for different values of m;

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP2QN05

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP2QN05

(a) (i) What is the difference between longitudinal and transverse waves?
(ii) State two distinctions between the way sound waves and electromagnetic waves are transmitted
(b) A mineworker stands between two vertical cliffs 400m from the nearest cliff. The cliffs are X distance apart. Every time he strikes the rock once, he hears two echoes, the first one after 2.5 s, while the second follows 2s later. From this information; calculation:
(i) The speed of the sound in air
(ii) The value of X
(c) In an experiment to observe interference of light waves a double slit is placed close to the source. See figure

(i) State the function of the double slit
(ii) Describe what is observed on the screen
(iii) State what is observed on the screen when
I. The slit separation S1S2 is reduced
II. White light source is used in place of monochromatic source

answers

(a) (i) Particles of the transmitting medium vibrate in the direction of the wave for a longitudinal wave, but at right angles for a transverse wave:Sound requires medium but no medium required for electromagnetic wave; speed of sound lower than that of electromagnetic wave;

(c) (i) Double slit provides coherent sources;
(ii) Dark and bright fringes;
The central fringe is the brightest while the intensity of the other fringes reduces away from the central fringe;
(iii) I. The separation of fringes increases
II. Central fringe is white; fringes on either side are colored;

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP2QN04

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP2QN04

(a) (i) Describe the experiment to determine the specific heat capacity C, of a block of aluminium with two holes drilled in it, to accommodate a thermometer and an electric immersion heater
(ii) State the measurements required in the experiment and show how they would be used to obtain C
(iii) State two precaution that should be taken in this experiment
(b) A copper calorimeter of mass 60g is filed with 100g of water at 25C. Steam at a normal temperature and pressure ( N.T.P) is passed thought the water until a temperature 45C is attained. The final mass of calorimeter and the contents was found to be 163.5g. Calculate the specific latent heat of vaporization â€žlâ€Ÿ of water Specific heat capacity for water is 4200JKg^-1 and for copper is 378Kg^-1K¹

answers

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP2QN03

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP2QN03

The diagram in fig 2 represent an electric circuit in which five resistors are connected to be a battery of e.m.f 4.0 V and of negligible internal resistance

Determine:
(i) The total resistance of the circuit
(ii) The potential difference between Y and Q

answers

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP2QN02

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP2QN02

(a) Given a bar magnet, an iron bar and a string
(i) Describe a simple experiment to distinguish between the magnet and the iron bar
(ii) State with reasons the observation that would be made in the experiment
(b) In an experiment to magnetize two substances P and Q using electric current, two curves ( graphs) were obtained as shown in figure

Using the information in Fig 1 explain the difference between the substances P and Q with references to the domain theory

answers

(a) (i) Each bar is suspended at a time using the string;
The suspended bar is allowed to rest;
Its orientation is observed and recorded;
This is repeated several times for confirmation
(ii) The bar magnet settles in the N – S specific direction, due to its
Interaction (l) with magnetic field of the earth (l)
The iron bar settles in any direction; (l) because it does not have a magnetic field to the interact with that of the earth; (l)
(b) P and Q are magnetized to the same level, by applying two different (l) current lp and lq such that lq > lp (l)
Thus Q requires greater magnetizing power, (l) since its domains are more difficult to align; (l) P is easier to magnetize, since its (l) domain are more easily aligned:

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP2QN01

5/7/2020

0 Comments

(a) 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
(b) A body moving initially at 50m/s decelerates uniformly at two 2ms^-2 until it comes to rest. What distance does it cover from the time it started to decelerate

answers

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN38

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN38

Figure 8 shows an object O placed in front of a concave lens with principal foci F and F Construct a ray diagram to locate the position of the image

ANSWERS

0 Comments

In the Brownian motion experiment, smoke particles are observed to move randomly. Explain how this motion is caused

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN37

In the Brownian motion experiment, smoke particles are observed to move randomly. Explain how this motion is caused

ANSWERS

Smoke particles are continually bombarded by invisible particles of air that are in constant random motion

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN33

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN33

α- particles are more ionizing than beta- particles. Give one reason for this

In the figure 7 the circuit diagram contains bulbs B, a transistor T and a resistor R. A diode D is connected between points Y and X as shown. In the set up bulb B is not lit. When the connections YP and XQ are made, B lights. Answer questions 34, 35 and 36 with reference to the figure.
Name the type of transistor used in the circuit
Explain the observation when the connections are made

answers

Low speed / high charge / more massive/ size is large/ bigger`
n-p-n
Limit the current through the base controls the current/ protect transistor from high current or voltage/ regulate reduce voltage.
Diode is forward biased; Base currents flows; hence collector current flows and lights the bulb/ current amplification air molecule are in constant random motion; smoke particles collide with these air molecules hence their random motion

0 Comments

The control grids in a cathode Ray Oscilloscope ( CRO) is used to control the brightness of the beam on the screen. How is this achieved?

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN32

The control grids in a cathode Ray Oscilloscope ( CRO) is used to control the brightness of the beam on the screen. How is this achieved?

ANSWERS

Low negative voltage is applied on control grid, which control the number of electrons reaching the screen

0 Comments

What causes electromagnetic damping in a moving coil galvanometer

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN31

What causes electromagnetic damping in a moving coil galvanometer

ANSWERS

Eddy current

0 Comments

The moment of the weight of vertical door does not significantly affect the moment of the force required to open the door. Give a reason for this

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN30

The moment of the weight of vertical door does not significantly affect the moment of the force required to open the door. Give a reason for this

ANSWERS

The weight of the door and the force are perpendicular to one another

0 Comments

A solid copper sphere will sink in water while a hollow copper sphere of the same mass many float. Explain this observation

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN29

A solid copper sphere will sink in water while a hollow copper sphere of the same mass many float. Explain this observation

ANSWERS

Solid copper is denser than water hence the solid sphere sinks; weight is greater than upthrust. Hollow sphere experiences an upthrust equal to its weight so it will float/ density of hollow sphere is less than that of water

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN28

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN28

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

ANSWERS

A hears a constant frequency produced by the siren/ same roundness/ pitch B hears a frequency that increases as the vehicle approaches/ sound of increasing loudness/ higher sound

0 Comments

Explain how a piece of a Polaroid reduces the sun's glare

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN27

Explain how a piece of a Polaroid reduces the sun's glare

ANSWERS

A Polaroid absorbs/ cuts off light waves in all planes except in a particular plane of propagation

0 Comments

A house in which as cylinder containing cooking gas is kept unfortunately catches fire. The cylinder explodes. Give an explanation for the exposition

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN26

A house in which as cylinder containing cooking gas is kept unfortunately catches fire. The cylinder explodes. Give an explanation for the exposition

ANSWERS

High temperature causes high – pressure build up in the cylinder, which causes the explosion; OR increases of KE of gas molecules which result to pressure, build up causing an explosion

0 Comments

In some petrol engines where spark plugs are used, a capacitor is connected to the distributor. Suggest the function of the capacitor.

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN25

In some petrol engines where spark plugs are used, a capacitor is connected to the distributor. Suggest the function of the capacitor.

ANSWERS

Maintaining a stable voltage during make and break/ storing charge during make and break and stops arcing sparking

0 Comments

State how the pressure in a moving fluid varies with the speed of the fluid

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN24

State how the pressure in a moving fluid varies with the speed of the fluid

ANSWERS

Pressure is inversely proportional to the speed OR speed increases as pressure distance

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN23

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN23

A small object lies at the bottom of a water pond at a depth of 1.2 m. Given that the refractive index of water is 1.3, determine the apparent dept of the object. (Give your answers to 1 decimal place)

ANSWERS

0 Comments

A lady holds a large concave of facal length 1 m, 80 cm from her face, state two characteristics of her image in the mirror

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN22

A lady holds a large concave of facal length 1 m, 80 cm from her face, state two characteristics of her image in the mirror

ANSWERS

Magnified, enlarged upright, virtual , image behind the mirror, negative distance

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN21

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN21

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.

ANSWERS

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN20

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN20

A girl heats 5 kg of water to temperature of 80C. When she adds m kg of water at 15 C the mixture attains temperature of 40C. Determine the value of m. (ignore heat changes due to the container)

answers

0 Comments

In large current circuits large resistors in parallel are preferred to low resistors in series explain

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN19

In large current circuits large resistors in parallel are preferred to low resistors in series explain

answers

Parallel resistor allow diversion of current; hence may not overheat; / current shared by parallel resistor

0 Comments

What characteristics of sound is applied in turning pianos?

5/7/2020

0 Comments

K.C.S.E Physics Q & A - MODEL 1996PP1QN18

What characteristics of sound is applied in turning pianos?

answers

Interferences

0 Comments

<<Previous

K.C.S.E Physics Q & A - MODEL 1996PP2QN07

(Speed of light, c = 3.00 * 108 ms-1 planks constant h = 6.663 * 10-34JS)

K.C.S.E Physics Q & A - MODEL 1996PP2QN06

K.C.S.E Physics Q & A - MODEL 1996PP2QN05

K.C.S.E Physics Q & A - MODEL 1996PP2QN04

K.C.S.E Physics Q & A - MODEL 1996PP2QN03

K.C.S.E Physics Q & A - MODEL 1996PP2QN02

K.C.S.E Physics Q & A - MODEL 1996PP1QN38

In the Brownian motion experiment, smoke particles are observed to move randomly. Explain how this motion is caused

K.C.S.E Physics Q & A - MODEL 1996PP1QN33

The control grids in a cathode Ray Oscilloscope ( CRO) is used to control the brightness of the beam on the screen. How is this achieved?

What causes electromagnetic damping in a moving coil galvanometer

The moment of the weight of vertical door does not significantly affect the moment of the force required to open the door. Give a reason for this

A solid copper sphere will sink in water while a hollow copper sphere of the same mass many float. Explain this observation

K.C.S.E Physics Q & A - MODEL 1996PP1QN28

Explain how a piece of a Polaroid reduces the sun's glare

A house in which as cylinder containing cooking gas is kept unfortunately catches fire. The cylinder explodes. Give an explanation for the exposition

In some petrol engines where spark plugs are used, a capacitor is connected to the distributor. Suggest the function of the capacitor.

State how the pressure in a moving fluid varies with the speed of the fluid

K.C.S.E Physics Q & A - MODEL 1996PP1QN23

A lady holds a large concave of facal length 1 m, 80 cm from her face, state two characteristics of her image in the mirror

K.C.S.E Physics Q & A - MODEL 1996PP1QN21

K.C.S.E Physics Q & A - MODEL 1996PP1QN20

In large current circuits large resistors in parallel are preferred to low resistors in series explain

What characteristics of sound is applied in turning pianos?

Categories

FORM I - PHYSICS SYLLABUS

FORM II - PHYSICS SYLLABUS

FORM III - PHYSICS SYLLABUS

FORM IV - PHYSICS SYLLABUS

Archives

M.A Nyamoti

HIGH SCHOOL RESOURCES

PRIMARY SCHOOL RESOURCES 8-4-4

PRIMARY SCHOOL RESOURCES CBC

COLLEGE RESOURCES

FREE NOVELS

(Speed of light, c = 3.00 * 108 ms^-1 planks constant h = 6.663 * 10^-34JS)