1
COMEDK 2023 Evening Shift
MCQ (Single Correct Answer)
+1
-0

The time dependence of a physical quantity P is give by $$\mathrm{P=P}_0 \exp \left(-\alpha t^2\right)$$ where $$\alpha$$ is a constant and $$t$$ is time. The constant $$\alpha$$ will

A
Have dimensions as that of $$\mathrm{P}$$
B
Have dimensions equal to that of $$\mathrm{Pt}^2$$
C
Have no dimensions
D
Have dimensions of $$t^{-2}$$
2
COMEDK 2023 Evening Shift
MCQ (Single Correct Answer)
+1
-0

The molecules of a given mass of a gas have root mean square speed of $$120 \mathrm{~m} / \mathrm{s}$$ at $$88^{\circ} \mathrm{C}$$ and 1 atmospheric pressure. The root mean square speed of the molecules at $$127^{\circ} \mathrm{C}$$ and 2 atmospheric pressure is

A
105.2 m/s
B
1.443 m/s
C
126.3 m/s
D
88/127 m/s
3
COMEDK 2023 Evening Shift
MCQ (Single Correct Answer)
+1
-0

The acceleration due to gravity at a height of $$7 \mathrm{~km}$$ above the earth is the same as at a depth d below the surface of the earth. Then d is

A
7 km
B
2 km
C
3.5 km
D
14 km
4
COMEDK 2023 Evening Shift
MCQ (Single Correct Answer)
+1
-0

A tentative explanation of observations without assuming that it is true is called

A
hypothesis
B
physical laws
C
theory
D
model
EXAM MAP