MCQ
The de Broglie wavelength $\lambda$ associated with a proton increases by $25 \%$, if its momentum is decreased by $p_0$. The initial momentum was
- A$4 p_0$
- B$\frac{p_0}{4}$
- ✓$5 p_0$
- D$\frac{p_0}{5}$
✓
Answer
Correct option: C.
$5 p_0$
c
(c)
(c)
$\frac{\lambda_2-\lambda_1}{\lambda_1}=\frac{25}{100}$
$\frac{\lambda_2}{\lambda_1}=\frac{5}{4} \Rightarrow \frac{P_1}{P_2}=\frac{5}{4}$
$P_2-P_1=-P_0$
$\frac{4 P_1}{5}-P_1=-P_0$
$P_1=5 P_0$
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
The focal lengths of the objective and eye lenses of a telescope are respectively $200 \,cm$ and $5 \,cm.$ The maximum magnifying power of the telescope will be
→The quantity of heat required to raise one mole through one degree Kelvin for a monoatomic gas at constant volume is
The wettability of a surface by a liquid depends primarily on
An engine pumps water continuously through a hose. Water leaves the hose with a velocity $v$ and $m$ is the mass per unit length of the water jet. What is the rate at which kinetic energy is imparted to water $?$
→An open cubical tank was initially fully filled with water. When the tank was accelerated on a horizontal plane along one of its side it was found that one third of volume of water spilled out. The acceleration was
If $A$ and $B$ are two inputs in $AND $ gate, then $AND$ gate has an output of $1$ when the values of $A$ and $B$ are
→Work done by restoring force in a string within elastic limit is $-10 \,J$. Maximum amount of heat produced in the string is .......... $J$
→A coil having an area $2\,{m^2}$ is placed in a magnetic field which changes from $1\,Wb/{m^2}$ to $4\,Wb/{m^2}$ in a interval of $2$ second. The $e.m.f.$ induced in the coil will be......$V$
→A current carrying rectangular loop PQRS is made of uniform wire. The length $PR = QS =5\,cm$ and $PQ = RS =100\,cm$. If ammeter current reading changes from I to $2 I$, the ratio of magnetic forces per unit length on the wire $P Q$ due to wire RS in the two cases respectively $f_{ PQ }^{ I }: f_{ PQ }^{2 I }$ is :
→A current $I$ flows in an infinitely long wire with cross-section in the form of a semicircular ring of radius $R$. The magnitude of the magnetic induction along its axis is
→