Heisenberg's Uncertainty Principle

Q.

The uncertainty in the position of an electron is zero, the uncertainty in its momentum be

1. Zero

2. 

3. 

4. Infinity

Q.

A golf ball has a mass of 40g and a speed of 45 m$s^{-1}$. If the speed can be measured with an accuracy of 2%, calculate the uncertainty in the position.

1. 2.62 × 10^-34 m

2. 1.46 × 10^-33 m

3. 5.55 × 10^-33 m

4. 4.84 × 10^-35 m

Q.

According to Heisenberg's uncertainty principle, the product of uncertainties in position and velocities for an electron of mass 9.1 $\times$ ${10}^{-31}$ kg is

1. 6.8 × 10^-6 m² s^-1

2. 5.8 × 10^-5 m² s^-1

3. 2.8 × 10^-3 m² s^-1

4. 3.8 × 10^-5 m² s^-1

Q.

Calculate the uncertainty in the position ($\Delta x)$ of an electron if $\Delta vis0.1\%$. Take the velocity of electron $=2.2\times {10}^{6}m{s}^{-1}$ and mass of electron as $9.108\times {10}^{-31}kg$.

1. 262.48 × 10^-10 m

2. 9.1 × 10^-9 m

3. 458.76 × 10^-12 m

4. 959.67 × 10^-10 m

Q. Uncertainties in the measurement of position and in momentum for an electron is $\Delta x\text{and}\Delta p$ respectively. It is given that the uncertainty in the measurement of velocity is $7.98\times {10}^{6}m/s$. Which of the following is correct?
$[\text{Given}:h/4\pi =0.527\times {10}^{-34}]$

1. $\frac{\Delta p}{\Delta x}\approx {10}^{10}$
2. $\frac{\Delta p}{\Delta x}\approx {10}^{20}$
3. $\frac{\Delta p}{\Delta x}\approx {10}^{-12}$
4. $\frac{\Delta x}{\Delta p}\approx {10}^6$

Q.

In an atom, an electron is moving with a speed of 600 m/sec with an accuracy of 0.005%. Certainty with which the position of the electron can be located is:

(h = 6.6 $\times$ ${10}^{-34}$ kg $m^3$ $s^{-1}$, mass of electron $m_e$ = 9.1 $\times$ ${10}^{-31}$ kg)

1. 1.52 × 10^-4 m

2. 1.92 × 10^-4 m

3. 5.1 × 10^-4 m

4. 3.84 × 10^-4 m

Q.

Uncertainity in position of a hypothetical subatomic particle is $1\AA$ and uncertainty in velocity is $\frac{3.3}{4\pi }\times {10}^{5}m/s$ then the mass of the particle is approximately $[h=6.6\times {10}^{-34}Js]$

1. 2× 10^-29 kg

2. 2 × 10^-27 kg

3. 2 × 10 ^-29 kg

4. 2 × 10^-28 kg

Q.

In an atom, an electron is moving with a speed of $600m/s$ with an accuracy of 0.005 %. Certainity with which the position of the electron can be located is

($h=6.6\times {10}^{-34}kg{m}^2{s}^{-1}$, mass of electron, $e^m=9.1\times {10}^{-31}kg$)

1. 

2. 

3. 

4. 

Q.

For a quantum particle like the electron - both its velocity and position could be measured simultaneously and with very good precision.

1. True

2. False

Q.

If uncertainty in the position of an electron is zero, the uncertainty in its momentum would be

1. Zero

2. 

3. 

4. Infinite