A Swedish watch company is assigning ID cards for its employees. The ID is made of 7 digits. How many ID numbers can exist such that at least one of the digits repeat?

I

is moment of inertia of a uniform square plate about an axis perpendicular to its plane and passing through its centre. The moment of inertia of that plate about an axis in the plane of plate making an angle

60^{o}

with side of plate and passing through centre is:

Q. If

\frac{a + i b}{c + i d} = p + i q

then

\frac{a - i b}{c - i d} = p - i q

Join BYJU'S Learning Program

The moment of inertia of a square plate about a diagonal is Id and that about a side in its plane is Is then

The correct option is C Is>IdThe moment of inertia is higher for a body if more mass is distributed away from the rotational axis. For a square rotating about a diagonal equal mass is distributed about its rotational axis, thus its moment of inertia will be lower.

The moment of inertia of a square plate about a diagonal is $I_{d}$ and that about a side in its plane is $I_{s}$ then

The correct option is C $I_{s} > I_{d}$
The moment of inertia is higher for a body if more mass is distributed away from the rotational axis. For a square rotating about a diagonal equal mass is distributed about its rotational axis, thus its moment of inertia will be lower.