JEE physics

A proton moves with velocity v = 3 × 10⁶ i m/s in a magnetic field B = 0.5 k T — JEE Physics

RRohanIyer58 Asked 30d ago 1,424 views 1 answer

A proton moves with velocity $\vec{v} = 3 \times 10^6\ \hat{i}$ m/s in a magnetic field $\vec{B} = 0.5\ \hat{k}$ T. Find the magnetic force on it. ($e = 1.6 \times 10^{-19}$ C)

1 Answer

VAVidaara Admin ✓ Vidaara Team ✓ Accepted · 30d ago ▲ 30

$$\vec{F} = q(\vec{v} \times \vec{B}) = 1.6\times10^{-19}(3\times10^6 \hat{i} \times 0.5\hat{k})$$

$$\hat{i} \times \hat{k} = -\hat{j}$$

$$\vec{F} = 1.6\times10^{-19} \times 1.5\times10^6 (-\hat{j}) = -2.4\times10^{-13}\ \hat{j} N$$

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Discussion (3)

DM
Underrated solution. The way you set it up makes it almost obvious.
Divya Mehta · 28d ago
MT
Does this approach generalise to the JEE Advanced version of this question?
Manish Tiwari · 27d ago
VA
Nicely solved. For the exam, write the final boxed answer clearly to avoid losing marks.
Vidaara Admin · Vidaara Team · 24d ago
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