JEE Mains · Physics · STD 12 - 11. Dual nature of radiation and matter
A small object at rest, absorbs a light pulse of power \(20\,mW\) and duration \(300\,ns\). Assuming speed of light as \(3 \times 10^8\,m / s\). the momentum of the object becomes equal to \(.........\times 10^{-17} kg\,m / s\)
- A \(0.5\)
- B \(2\)
- C \(3\)
- D \(1\)
Answer & Solution
Correct Answer
(B) \(2\)
Step-by-step Solution
Detailed explanation
Momentum \(=\frac{\text { Energy }}{ C }\) \(=\frac{\text { Power } \times \text { time }}{ C }\) \(=\frac{\left(20 \times 10^{-3} w \right)\left(300 \times 10^{-9}\,s \right)}{3 \times 10^8 m / s }\) \(=2 \times 10^{-17}\,kg - m / s\)
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Physics
- The pressure acting on a submarine is \(3 \times 10^{5}\;Pa\) at a certain depth. If the depth is doubled, the percentage increase in the pressure acting on the submarine would be: (Assume that atmospheric pressure is \(1 \times 10^{5} \;Pa\) density of water is \(10^{3}\, kg \,m ^{-3}, g =10 \,ms ^{-2}\) )JEE Mains 2021 Medium
- A wire of resistance \(R\) and radius \(r\) is stretched till its radius became \(r / 2\). If new resistance of the stretched wire is \(xR\), then value of \(x\) is _______.JEE Mains 2024 Hard
- A current of \(30\) A each flows in opposite directions in two conducting wires, placed parallel to each other at a distance of \(8\) cm. The magnetic field at the mid point between the two wires is __________ \(\mu\)T. \(\left(\dfrac{\mu_0}{4\pi} = 10^{-7}\text{ N/A}^2\right)\)JEE Mains 2026 Medium
- The angle of projection for a projectile to have same horizontal range and maximum height is _______.JEE Mains 2024 Hard
- A sample of an ideal gas is taken through the cyclic process \(abca\) as shown in the figure. The change in the internal energy of the gas along the path \(ca\) is \(-180\, J\). The gas absorbs \(250\, J\) of heat along the path \(ab\) and \(60\, J\) along the path \(bc\). The work done by the gas along the path \(abc\) is ..... \(J\)
JEE Mains 2019 Medium - Solid sphere \(A\) is rotating about an axis \(PQ\). If the radius of the sphere is \(5\,cm\) then its radius of gyration about \(P Q\) will be \(\sqrt{x} \;cm\). The value of \(x\) is \(................\).
JEE Mains 2023 Medium
More PYQs from JEE Mains
- The coercivity of a magnet is \(5 \times 10^3 \mathrm{~A} / \mathrm{m}\). The amount of current required to be passed in a solenord of length \(30 \mathrm{~cm}\) and the number of turns \(150\) , so that the magnet gets demagnetised when inside the solenoid is _______ A.JEE Mains 2024 Hard
- The constant term in the expansion of \(\left(2 x+\frac{1}{x^7}+3 x^2\right)^5 \text { is }........\).JEE Mains 2023 Hard
- A line is a common tangent to the circle \((x-3)^{2}+y^{2}=9\) and the parabola \(y^{2}=4 x.\) If the two points of contact \(( a , b )\) and \(( c , d )\) are distinct and lie in the first quadrant, then \(2(a+c)\) is equal to ........ .JEE Mains 2021 Hard
- Two vectors \(\overrightarrow{{X}}\) and \(\overrightarrow{{Y}}\) have equal magnitude. The magnitude of \((\overrightarrow{{X}}-\overrightarrow{{Y}})\) is \({n}\) times the magnitude of \((\overrightarrow{{X}}+\overrightarrow{{Y}})\). The angle between \(\overrightarrow{{X}}\) and \(\overrightarrow{{Y}}\) is -JEE Mains 2021 Hard
- Let \(\mathrm{Y}=\mathrm{Y}(\mathrm{X})\) be a curve lying in the first quadrant such that the area enclosed by the line \(Y-y=Y^{\prime}(x)(X-x)\) and the co-ordinate axes, where \((\mathrm{x}, \mathrm{y})\) is any point on the curve, is always \(\frac{-y^2}{2 Y^{\prime}(x)}+1, Y^{\prime}(x) \neq 0\). If \(Y(1)=1\), then \(12 Y(2)\) equalsJEE Mains 2024 Hard
- A lift of mass \(1600\) kg is supported by thick iron wire. If the maximum stress which the wire can withstand is \(4 \times 10^8\) N/m\(^2\) and its radius is \(4\) mm, then maximum acceleration the lift can take is _______ m/s\(^2\). (take \(g = 10\) m/s\(^2\) and \(\pi = 3.14\))JEE Mains 2026 Medium