$P, Q$ and $R$ are long parallel straight wires in air, carrying currents as shown. The direction of the resultant force on $R$ is:

Three rods of same dimensions have thermal conductivities $3K$,$2K$,and $K$. They are arranged as shown in the figure. In the steady state,the temperature of the junction $P$ is

The area (in square units) of the triangle formed by the lines $x=0$,$y=0$ and $3x+4y=12$ is:

The major product in the following reaction is:

$A$ ray of light of intensity $I$ is incident on a parallel glass slab at point $A$ as shown in the diagram. It undergoes partial reflection and refraction. At each reflection, $25\%$ of incident energy is reflected. The rays $AB$ and $A'B'$ undergo interference. The ratio of $I_{max}$ and $I_{min}$ is (in $: 1$)

The variation of radiant energy emitted by the sun, the filament of a tungsten lamp, and a welding arc as a function of its wavelength is shown in the figure. Which of the following options is the correct match?