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.
Which of the following statements about kinetic theory of matter is not correct?
The molecules of matter are always in motion
When a body is heated the average kinetic energy of its molecules decreases
Molecules of a liquid move more freely than those of a solid
Matter is made up of very tiny particles called molecules
The molecules of a gas move more freely than those of a liquid
Correct answer is B
No explanation has been provided for this answer.
4.5 x \(10^{10}\)Hz
5 x \(10^{9}Hz\)
4.5 x \(10^{8}Hz\)
2 x \(10^{7}Hz\)
2 x \(10^{6}Hz\)
Correct answer is E
V=f\(\lambda, f =\frac{v}{\lambda}= \frac{3\times10^8}{150}\Rightarrow 2\times10^6\)Hz
15 minutes
20 minutes
42 minutes
50 minutes
84 minutes
Correct answer is D
H=pt =mL +mcθ ; 840t= 100x336+100x4.2x20 thus t=420000/840=50minutes
37.5cm
22.5cm
15cm
7.5cm
3.3cm
Correct answer is A
If u=x, v = \(1\frac{1}{2}x \Rightarrow if u= 2x,v=3x\\
\frac{1}{f}=\frac{1}{u}+\frac{1}{v}; \frac{1}{15}=\frac{1}{2x}+\frac{1}{3x} \times \frac{5}{6}\\
X=\frac{75}{76}=12.5, v=3x=12.5\times 3=37.5\)
2.5\(cm^3\)
15.5\(cm^3\)
18.7\(cm^3\)
21.4\(cm^3\)
72.5\(cm^3\)
Correct answer is C
\(v_2=\frac{v_1p_1}{p_2}=\frac{20\times700}{750}=18.66=18.7cm^3\)