An alpha particle is projected vertically upward a speed of `3.0 X 10^4 km s^(-1)` in a region where a magnetic field of magnitude 1.0 T exists in the direction south to north. Find the magnetic force that acts on the a particle.

Explanation

To solve the problem of finding the magnetic force acting on an alpha particle projected vertically upward in a magnetic field, we can follow these steps:

### Step 1: Understand the parameters given in the problem.
- **Speed of the alpha particle (v)**: \(3.0 \times 10^4 \, \text{km/s}\)
- **Magnetic field (B)**: \(1.0 \, \text{T}\) (from south to north)
- **Charge of the alpha particle (Q)**: An alpha particle consists of 2 protons and 2 neutrons, so its charge is \(Q = 2 \times 1.6 \times 10^{-19} \, \text{C}\).

### Step 2: Convert the speed from km/s to m/s.
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