For a uniform rectangular sheet shown in the figure, the ratio of moments of inertia about the axes perpendicular to the sheet and passing through (the centre of mass) and (corner point) is:
A dip needle lies initially in the magnetic meridian when it shows an angle of dip at a place. The dip circle is rotated through an angle in the horizontal plane and then it shows an angle of dip . Then is
r=b+cπθ for 0≤θ≤π2
Here b and c are positive constants. θ is the angle measured with respect to positive X direction in anticlockwise sense and r is the distance from origin (see figure). The magnetic field at the origin due to the wire is found to be μoIxcln(1+cyb)
The value of xy is
Declination is the angle between:
horizontal and vertical components of earth’s magnetic field
geographic and magnetic meridian
horizontal component and total magnetic field of the earth
geographic meridian and horizontal component of earth's magnetic field
In the magnetic meridian of a certain place, the horizontal component of earth's magnetic field is 0.25 gauss and the dip angle is 60o. At this place find the value of earth's magnetic field.
- The magnetic field near the poles is zero.
- The magnetic field near the poles is almost vertical.
- At low temperature, the compass needle looses its magnetic properties.
- None of these
(a) its normal bisector and (b) its axis. Magnitude of the earths field at the place is given to be 0.42G. Ignore the length of the magnet in comparison to the distances involved
- None of these
A line joining places of equal horizontal field is called
- 0.50 G
- 0.000025 G
- 1.25 G
- 2.50 G
(1) Blv sin θ (2) Blv tan θ (3) Blv cot θ (4) Blv cos θ
define magnetic declination
A line joining places of same declination is called