Physics Questions and Answers
If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.
If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.
The velocity of a sound wave at 27oC is 360ms-1. Its velocity at 127oC is
120√3 ms-1
240 ms-1
240√3 ms-1
720√3 ms-1
Correct answer is C
Velocity \(\alpha \sqrt{temperature}\)
\(\frac{V_1}{V_2} = \sqrt{\frac{T_1}{T_2}}\)
therefore, \(\frac{360}{V_2} = \sqrt{\frac{27 + 273}{127 + 273}}\)
\(V_2 = 240\sqrt{3}\)m/s
450ms-1
400ms-1
300ms-1
250ms-1
Correct answer is C
F = ma
Therefore, a = \(\frac{F}{m}\)
a = \(\frac{7.5 \times 10^{3}}{0.025}\)
a = 3 x 105m/s2
using V2 = U2 + 2ax;
V2 = 02 + (2 x 3 x 105 x 0.15)
Therefore V = 300 m/s
I,II and lll only
ll,lll and lV only
l, II and lV only
l, ll, lll and lV
Correct answer is C
No explanation has been provided for this answer.
If a reverse-biased voltage is applied across a p-n junction, the depletion layer width is
increased
decreased
constant
halved
Correct answer is B
No explanation has been provided for this answer.
The p-n junction diodes can act as rectifiers because they
conduct current when forward-biased
conduct current when reverse-biased
block current when forward-biased
conduct current in both directions
Correct answer is A
No explanation has been provided for this answer.