A charged particle moving in a constantmagnetic field always experiences a magnetic force, regardless of its direction of motion. • may experience a magnetic force which will cause its speed to change. • may experience a magnetic force, but its speed will not change

A charged particle moving in a constant magnetic field may experience a magnetic force but its speed will not change.

Explanation:

The magnetic force experienced by a charged particle q that moves in a magnetic field with velocity is:

and its magnitude is given by:

where is the angle between the magnetic field and the velocity.

There are two special cases:

The magnetic force is always perpendicular to the velocity. The work done by the magnetic force is equal to the force multiplied by the displacement in the direction of the force:

Given that the work is equal to the change in kinetic energy and this means the speed will not change.

see earlier answer

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards