Physics (2017) | Study Mode

Join Discuss Share to WhatsApp
Question 41
A

5

B

4

C

3

D

2

Explanation

When two mirror are inclined at an angle \(\theta\), the number of images formed, n = \(\frac{360}{\theta}\) - 1

since \(\theta\) = 90o

\(\frac{360}{\theta}\) - 1

= 4 - 1

= 3


Correct option: C
Join Discuss Share to WhatsApp
Question 42
A
Zener material
B
P-n junction
C
n-type
D
p-type
Explanation
When silicon is doped with a trivalent atom. A p-type semi-conductor will be formed when silicon is doped with a pentavalent atom such as arsenic, a n-type semi-conductor will be formed
Phosphorous is a pentavalent element, so it will produce a o -type semi-conductor

Correct option: C
Join Discuss Share to WhatsApp
Question 43
A
N80.00
B
N45.36
C
N65.00
D
N57.12
Explanation
Seven 40W lamps = 7 \(\times\) 40 = 280W

Five 80W lamps = 5 \(\times\) 80 = 400W

Total power = 280W + 400W

= 680W

= \(\frac{680KW}{1000}\) = 0.68KW

The kilowatt hour = 0.68 KW \(\times\) 12 hrs

= 8.16 KWh

Cost is N 7 per KWh

So the cost of running them = 8.16KWh \(\times\) N 7/KWh

= 57.12

Correct option: D
Join Discuss Share to WhatsApp
Question 44
Physics (2017) Q 45 image
A

5.0A

B

3.7A

C

4.5A

D

4.0A

Explanation
V = IR from ohms law

I = \(\frac{V}{R}\)

Since the resistance are in parallel

\(\frac{1}{Reff}\) = \(\frac{1}{8}\) + \(\frac{1}{12}\) + \(\frac{1}{6}\)

= \(\frac{2 + 3 + 6}{36}\) = \(\frac{11}{36}\)

Reff = \(\frac{36}{11}\) = 3.27

I = I1 + I2 + I3

= \(\frac{V}{Reff}\)= \(\frac{12}{3.27}\)

= 3.669A

I = 3.7A

Correct option: B
Join Discuss Share to WhatsApp
Question 45
A

10s

B

5s

C

4s

D

2s

Explanation
u = ?, H = 20, g = 10

From equation of motion under gravity

H = ut \(\frac{1}{2}\)gt2, It is falling so g is +ve

H = 0 + \(\frac{1}{2}\)gt2

H = \(\frac{1}{2}\)gt2

2H = gt2

\(\frac{2H}{g}\) = t2

t = \(\frac{\sqrt{2H}}{g}\)

= \(\frac{\sqrt {2 \times 20}}{10}\)

= \(\sqrt{4}\)

= 2s

Correct option: D
Join Discuss Share to WhatsApp
Question 46
A
wave in closed pipe
B
radio waves
C
water waves
D
sound waves
Explanation
Mechanical waves require material medium for their propagation only radio waves among the options docs require a material medium

Correct option: B
Join Discuss Share to WhatsApp
Question 47
A
Sin?
B
Cos?
C
Tan?
D
\(\frac{1}{\sin \theta}\)
Explanation
Consider an inclined plane shown below, as the effort moves along OB, the load moves is lifted up through a vertical height AB

V.R = \(\frac{\text{distance moved by effort}}{\text{distance moved by load}}\) = \(\frac{OB}{AB}\)

But Sin? = \(\frac{opp}{hyp}\) = \(\frac{AB}{OB}\)

therefore; = \(\frac{OB}{AB}\) = \(\frac{1}{\sin \theta}\)

Correct option: D
Join Discuss Share to WhatsApp
Question 48
A
30cm3
B
40cm3
C
50cm3
D
20cm3
Explanation
Using boyle's law

P1V1 = P2V2

V2 = \(\frac{P_1 V_1}{200}\) = \(\frac{400 \times 10}{200}\)

= 20cm3

Correct option: D
Join Discuss Share to WhatsApp
Question 49
A
\(^{58}_{28}X\)
B
\(^{30}_{28}X\)
C
\(^{28}_{30}X\)
D
\(^{58}_{30}X\)
Explanation
An atom can be represented thus,

\(^{Z}_{A}X\) where Z = mass number

A = atomic number

A = number of proton = number of electrons in a free state = 28

Z = number of protons + number of neutrons = 28 + 30 = 58

\(^{58}_{28}X\)is the representation

Correct option: A
Join Discuss Share to WhatsApp
Question 50
A
38.00o
B
19.47o
C
16.25o
D
49o
Explanation
For a refractive index () = \(\frac{\sin\frac{1}{2} (A + D)}{\sin\frac{1}{2}A}\)

D = angle of minimum deviation

A = refractive angle of the prism

1.5 = \(\frac{\sin\frac{1}{2} (60 + D)}{\sin\frac{1}{2} \times 60}\)

1.5 = \(\frac{\sin\frac{1}{2} (60 + D)}{\sin 30}\)

Sin \(\frac{1}{2}\) (60 + D) = 1.5 * Sin 30

Sin \(\frac{1}{2}\) (60 + D) = 0.75

\(\frac{1}{2}\) (60 + D) = Sin-1 (0.75)

but Sin-1 (0.75) = 49o

\(\frac{1}{2}\) (60 + D) = 49

60 + D = 2 * 49 = 98o

D = 98o - 60o

D = 38o

Correct option: A

Try this quiz in in E-test/CBT Mode
switch to Physics (2017) in CBT Mode

Previous Page Next Page
Question Map
Quiz link
Share Physics (2017) with your audience
Share to WhatsApp CBT mode Study mode copy link
​​​Help keep QUIZZERWEB running! 
A donation makes a contribution towards the costs, the time and effort that's going on in building and improving this platform.
 
Donate
​​​sponsored
Are you a writer, proof-reader, interpreter, teacher, student or just someone who works in Yorùbá Language? 
 
Translate those figures and numbers to words in standard Yoruba Language at YorubaNumeral.com.ng at no cost. 
 
It also aids learning the yoruba numbering system by providing detailed explanation for each number translated up to 25 billion. 
 
English to Yorùbá Numeral Translator