400N
200N
100N
800N
Correct answer is D
let the masses of the two objects be M1 and M2
and their distance apart = r
Therefore the force acting F1 = \( \frac{GM1M2}{r^2} \)
for a new distance of r/2, we have a force of
F2 = \( \frac{GM2M2}{r/2} \\
\text{Thus } F1 \times r^2 = GM1M1 \text{and} \\
F2 \times (r/2)^2 = GM1M1 \\
\text{Since } GM1M1 = GM1M1 \\
\implies F1 \times r^2 = F2 \times (r/2)^2 \\
\text{Therefore } 200 \times r^2 = F2 \times r^2/4 \\
F2 = \frac{4 \times 200 \times r^2}{r^2} = 800N \)
The velocity of sound in air will be doubled if it's absolute temperature is
Quadrupled
Constant
Halved
Doubled
Correct answer is A
In general, the velocity of sound in air varies directly as the square root of temperature measured in kelvin.
That V \( \propto \sqrt{T} \implies V^2 \propto T. \\
\text{Therefore} \frac{V^2_1}{T_1} = \frac{V^2_2}{T_2} \\
\text{Thus Let } V_1 = 4m/s \\
T_1 = 10K \\
\text{Therefore } V_2 = 2V_1 = 8m/s \\
\implies \frac{4^2}{10} = \frac{8^2}{T_2} \\
T_2 = \frac{64 \times 10}{16} = 40K\\
T_2 = 4T_1 \)
Thus when the velocity of sound in air is doubled, it's absolute temperature will be quadrupled.
5:3
1:50
50:1
3:5
No Correct Option
Correct answer is E
No explanation has been provided for this answer.
In an A.C circuit, the ratio of r.m.s value to peak value of current is
2
\( \frac{1}{2} \)
\( \frac{1}{\sqrt{2}} \)
\( \sqrt{2} \)
Correct answer is C
Irms = \( \frac{I_0}{\sqrt{2}} \)
\( \text{Therefore } \sqrt{2Irms} = I_0 \\
\frac{Irms}{I_0} = \frac{1}{\sqrt{2}} \)
Graham's Law
Boyle's Law
Pressure law
Charles Law
No Correct Option
Correct answer is E
Rate of diffusion is inversely proportional to the square root of density - Graham's law
\( P \propto \frac{1}{v} \) at constant temperature - Boyle's law
\( P \propto T \) at constant volume - Pressure law
\( P \propto T \) at constant pressure - Charles law
therefore no correct option