The force on a north pole, `vec F = m vec B`, is parallel to the field `mvec B`, is parallel to the field `vet B`. Does it contradict our earlier knowledge that a magnetic field can exert forces only perpendicular to itself?

Two bar magnets are placed close to each other with their opposite poles facing each other. In absence of other forces, the magnets are pulled towards each other and their kinetc energy increases. Does it contradict our earlier knowledge that magnetic forces cannot do any work and hence cannot increase kinetic energy of a system?

The net charge in a current carrying wire is zero. Them, why does a magnetic field exert a force on it?

An electric field (vec E) and a magnetic field (vec B)exist in a region . The fields are not perpendicular to each other.

Initially plane of coil is parallel to the uniform magnetic field B. In time Deltat it makes to perpendicular to the magnetic field, then charge flows in Deltat depends on this time as -

A charge q moves region in a electric field E and the magnetic field B both exist, then the force on its is

The force on a charged particle moving in a magnetic field can be computed as the vector sum of the force due to each separate component of the magnetic field. As an example, a particle with charge q is moving with speed v in the -y direction. It is moving in a uniform magnetic field vec B = B_x hat i + B_y hat j + B_z hat k. a. What are the components of the force vec F exerted on the particle by the magnetic field? b. If qgt0 , what must the signs of the components of vec B be if the components of vec F are all non-negative? c. If qlt0 and B_x = B_y = B_z gt 0, find the direction and magnitude of vec F in terms of |q|, v and B_x.

An alpha particle moving with the velocity vec v = u hat i + hat j ,in a uniform magnetic field vec B = B hat k . Magnetic force on alpha particle is

Let vec a , vec ba n d vec c be three units vectors such that 2 vec a+4 vec b+5 vec c=0. Then which of the following statement is true? a. vec a is parallel to vec b b. vec a is perpendicular to vec b c. vec a is neither parallel nor perpendicular to vec b d. none of these

A velocity filter uses the properties of electric and magnetic field to select particles that are moving with a specifice velocity. Charged particles with varying speeds are directed into the filter as shown. The filter consistt of an electric field E and a magnetic field B, each of constant magnitude, directed perpendicular to each other as shown, The charge particles will experience a force due to electric field given by F = qE. If positively charged particles are used, this force is towards right. The moving particle will also experience a force due to magnetic field given by F = qvB . When forces due to the two fields are of equal magnitude, the net force on the particle will be zero, the particle will pass through centre with its path unaltered. The electric and magnetic fields can be adjusted t choose the specific velocity to be filtered. The efect of gravity can be neglected. The electric and magnetic fields are adjusted to detect particles with positive charge q of certain speed v_(0) . which of the following expressions is equal to this speed?

A bar magnet of magnetic moment vec(M) is placed in a magnetic field of induction vec(B) . The torque exerted on it is