271.
A.
100oC
B.
248oC
C.
250oC
D.
350oC
Correct answer is C
tθ - to = 10,
t100 - to = 4
| θ | = | tθ - to
t100 - to |
× | 100 |
| 10
4 |
× | 100 | = | 250°C |
273.
A supply of 400V is connected across capacitors of 3μf and 6μf in series. Calculate the charge
A.
8 x 10−4C
B.
4 x 10−2C
C.
8 x 10−3C
D.
4 x 10−8C
Correct answer is A
| CT | = | C1 × C2
C1 + C2 |
| = | 3 × 6
3 + 6 |
= 189 = 2μf
Q = CV
⇒ 2 × 10−6 × 400
⇒ 800 × 10−6C = 8 × 10−4C
275.
Aluminium is sometimes used as the leaf of an electroscope because it
A.
is a light material
B.
is a good conductor
C.
is a good insulator
D.
can be converted into thin sheets
Correct answer is D
- Aluminium can be made in thin sheet like Gold.
- the leaf is a thin material that can be diverged easily.
JAMB Subjects
Aptitude Tests