Question
Two parallel wires carry equal currents of 10A along the same direction and are separated by a distance of 2.0cm. Find the magnetic field at a point which is 2.0cm away from each of these wires
✓
Answer
$\cos\theta=\frac{1}{2},$$\theta=60^\circ\ \&\ \angle\text{AOB}=60^\circ$
$\text{B}=\frac{\mu_0\text{I}}{2\pi\text{r}}=\frac{10^{-7}\times2\times10}{2\times10^{-2}}=10^{-4}\text{T}$
So net is $[(10^{-4})^2]+(10^{-4})^2+2(10^{-8})\cos60^\circ]^\frac{1}{2}$
$=10^{-4}\Big[1+1+2\times\frac{1}{2}\Big]^\frac{1}{2}$
$=10^{-4}\times\sqrt3\text{T}$
$=1.732\times10^{-4}\text{T}$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
A 100W bulb has tungsten filament of total length 1.0m and radius $4 \times 10^{-5}m$. The emissivity of the filament is 0.8 and $\sigma=6.0\times10^{-8}\text{Wm}^{-2}\text{K}^4.$ Calculate the temperature of the filament when the bulb is operating at correct wattage.
→If this telescope is used to view a 100 m tall tower 3 km away, what is the height of the image of the tower formed by the objective lens?
A flint glass prism and a crown glass prism are to be combined in such a way that the deviation of the mean ray is zero. The refractive index of flint and crown glasses for the mean ray are 1.620 and 1.518 respectively. If the refracting angle of the flint prism is 6.0°, what would be the refracting angle of the crown prism?
A rectangular wire frame, shown below, is placed in a uniform magnetic field directed upward and normal to the plane of the paper. The part AB is connected to a spring. The spring is stretched and released when the wire AB has come to the position A′ B′ (t = 0) How would the induced emf vary with time? Neglect damping.
Average lifetime of a hydrogen atom excited to n = 2 state is $10^{-8}s$. Find the number of revolutions made by the electron on the average before it jumps to the ground state.
→Obtain the formula for the electric field due to a long thin wire of uniform linear charge density λ without using Gauss’s law.
[Hint: Use Coulomb’s law directly and evaluate the necessary integral.]
[Hint: Use Coulomb’s law directly and evaluate the necessary integral.]
Three capacitors of capacitances 2 pF, 3 pF and 4 pF are connected in parallel.
- What is the total capacitance of the combination?
- Determine the charge on each capacitor if the combination is connected to a 100 V supply.
What is the shape of the wavefront in each of the following cases:
- Light diverging from a point source.
- Light emerging out of a convex lens when a point source is placed at its focus.
- The portion of the wavefront of light from a distant star intercepted by the Earth.
How many time constants will elapse before the charge on a capacitors falls to 0.1% of its maximum value in a discharging RC circuit?
