PHYSICS PAPER 3 - 2019 LANJET JOINT MOCK EXAMINATION

Share via Whatsapp

QUESTION 1

You are provided with the following apparatus:

  • Ammeter
  • Voltmeter
  • Mounted resistance wire labeled W
  • A new dry cell
  • A cell holder
  • 8 connecting wires
  • A switch
  • A jockey
  • Micrometer screw gauge (to be shared)

PART A
PROCEED AS FOLLOWS:

  1. Connect your apparatus as shown in the figure
    phyc3 q1a
  2. Place the jockey at L=10cm, close the switch S. Read and record the current and the P.d readings.                                                
    Current (I) =……………A                                                             (1/2mk)
    P.d (V) =………………….V                                                             (1/2mk)
  3. Repeat the procedure in (b) for other values of L, and complete the table below. (5mks)

    length L(cm)

    10

    15

    20

    25

    30

    35

    P.d.(V)

               

    Current I(A)

               
  4. Plot a graph of p.d (V) against current (I) in the graph paper provided. (5mks)
    Webp.net compress image 1
  5. Determine the slope S of the graph (3mks)
  6. Given that the relationship between p.d (V) and current (I) supplied from the cell is given by the equation E=V+Ir, use your graph to determine the values of
    E=………………… (1mk)
    r=………………… (1mk)

PART B

Re-arrange the apparatus as show below
phyc3 q1b

  1. Close the switch S and record the current, (I) and the P.d (V) readings.
    I=………………………A
    V=………………………V                                        (1mk)
  2. Use your values in (f) above to calculate the resistance R, of the wire, W.
    R=………………Ω                                                                (1mk)
  3. Measure the diameter d of the wire, W, using a micrometer screw gauge. Give your answer in SI units.
    d=………………….                                                              (1mk)
  4. Given that R= 4Ɓ/(πd^2 ), find the value of Ω for the wire W.              (1mk)

QUESTION 2

You are provided with the following apparatus:

  • A 250cm3 glass beaker
  • A candle
  • A metre rule
  • White screen
  • Water

PROCEED AS FOLLOWS:

  1. Set up the apparatus as shown in the figure below.
    phyc3 q2a
  2. Put about 200cm3of water into the beaker. Measure the height, h of the water above the base of the beaker.
  3. Given the internal radius, r of the beaker is given by the relation r=√(100/h) . Find the value of r.
    r =……………cm              (2mks)
  4. Adjust the position of the screen until a sharp image is formed on the screen.
    Read and record the corresponding values of U and V In the table below. Given that U = 10r, 9r, 8r… (8mks)
     

    10r

    9r

    8r

    7r

    6r

    5r

    4r

    3r

    U (cm)

                   

    V(cm)

                   
  5. Plot a graph of u against v. (5mks)
    Webp.net compress image 1
  6. Determine the slope at 6r. (3mks)


MARKING SCHEME

PART A

L(CM)

10

15

20

25

30

35

P.d (V)

1.00

1.10

1.15

1.20

1.25

1.30

I(A)

0.40

0.32

0.28

0.24

0.20

0.16

phyc3 parta ms

phyc3 parta ms2 Ogllk

 

QUESTION 2
H=3.0 cm
r=5.77cm

 

10r

9r

8r

7r

6r

5r

4r

3r

U(cm)

17.3

22.8

28.7

33.8

39.3

44.8

50.3

54.1

V(cm)

16.9

13.7

11.9

11.7

10.7

10.2

10.1

10.0

phyc3 q2 msssss
Gradient of tangent at 6r
Slope = change in y /change in x
Answer without unit


Download PHYSICS PAPER 3 - 2019 LANJET JOINT MOCK EXAMINATION.


Tap Here to Download for 50/-




Why download?

  • ✔ To read offline at any time.
  • ✔ To Print at your convenience
  • ✔ Share Easily with Friends / Students


Join our whatsapp group for latest updates
Get on WhatsApp Download as PDF
.
Subscribe now

access all the content at an affordable rate
or
Buy any individual paper or notes as a pdf via MPESA
and get it sent to you via WhatsApp

 

What does our community say about us?

Join our community on:

  • easyelimu app
  • Telegram
  • facebook page
  • twitter page
  • Pinterest