From the momentum conservation we know that the initial momentum is equal to the final momentum. The momentum in a singular way can be defined as the product between the mass and the velocity of an object. In the presented system, however, there are two objects, therefore the mass of both and the speed of both, before and after the collision must be taken into account. Mathematically we could describe this as

Here,
= Mass of each object
= Initial velocity of each object
= Final velocity of each object
From here we can realize that it is necessary to use the system on both cars to be able to predict what will happen either with their masses, or their speeds.
The correct answer is C.
Answer:
Explanation:
If I am not wrong
current = charge/time
All you have to take care of is the units should be in the same system
so
current = 12/(2*60) --------- 2 min = 2*60 sec
current = 12/120 = 0.1 amp
The magnetic force (Lorentz force) experienced by the proton in the magnetic field is given by

since

, because the velocity v and the force F in this problem are perpendicular, and so also the angle

between the velocity and the magnetic field B should be

.
Let's find the magnitude of the magnetic field; this is given by

To understand the direction, let's use the right-hand rule:
-index finger: velocity
- middle finger: magnetic field
- thumb: force
Since the velocity (index) points east and the force (thumb) points south, then the magnetic field (middle finger) points downwards. So we write:
B = -0.091 T