What potential difference is needed to accelerate a


Asked by maham237 @ in Physics viewed by 264 People


What potential difference is needed to accelerate a he+ ion (charge +e, mass 4u) from rest to a speed of 1.0×106 m/s ? express your answer using two significant figures?

Answered by maham237 @



For the law of conservation of energy, the loss in potential energy of the He+ ion should be equal to the gain in kinetic energy:
-\Delta U=\Delta K
which can be rewritten as
-q \Delta V =  \frac{1}{2}mv^2
where
q=+e = 1.6 \cdot 10^{-19}C is the charge of the ion,
m=4u=4\cdot 1.67 \cdot 10^{-27}kg is the mass of the ion,
v=1.0 \cdot 10^6 m/s is the speed of the ion.
By using these values, we find the potential difference needed:
\Delta V =  \frac{1}{2}  \frac{mv^2}{-q}= \frac{1}{2} \frac{(4\cdot 1.67 \cdot 10^{-27}kg)(1.0 \cdot 10^6 m/s)^2}{-1.6 \cdot 10^{-19}C}=   -20875 V=-21 kV
and the negative sign means the final point is at lower voltage than the initial point, and this is correct, because the ion has positive charge and a positive charge travels naturally from higher voltages to lower voltages.

Similar Questions

What is the difference between needs and wants in business

Asked by admin @ in Business viewed by 300 persons

What is the difference between needs, wants and demand

Si unit of potential difference

Asked by admin @ in Physics viewed by 322 persons

7. SI Unit of potential difference and e.m.f.is________​

When 5v potential difference is applied across a wire

Asked by admin @ in Physics viewed by 484 persons

When 5V potential difference is applied across a wire of length 0.1, the drift speed of electrons is 2.5× 10-4m/s if the electron density in the wire is 8× 1028m-3, …

How will you conclude that the same potential difference

Asked by admin @ in Physics viewed by 377 persons

how will you conclude that the same potential difference exists across three resistors connected in a parallel arrangement to a battery

A proton accelerated through a potential difference of 100v

Asked by admin @ in Physics viewed by 395 persons

A proton is accelerated through a potential difference of 400V to have same de broglie wavelength what potential difference must be applied across doubly ionised 8O16 atom A.50V. B.12.5V C.100V. …

What do you understand by the term potential difference

Asked by admin @ in Physics viewed by 337 persons

Question 16: (a) What do you understand by the term “potential difference” ? (b) What is meant by saying that the potential difference between two points is 1 volt ? …

What is the relationship between power current and potential difference

Asked by admin @ in Physics viewed by 324 persons

What is the relationship between power, current and potential difference

What is the potential difference across the 10 ? resistor

Asked by admin @ in Physics viewed by 333 persons

What will be the potential difference across 10 ohm resistor?

What is the potential difference vc−va?

Asked by maham237 @ in Physics viewed by 310 persons

It takes 3.0 μJ of work to move a 17 nC charge from point A to B. It takes -6.5 μJ of work to move the charge from C to …

What was the potential difference that stopped the proton?

Asked by maham237 @ in Physics viewed by 318 persons

Proton with an initial speed of 800000 m/s is brought to rest by an electric field. Part A- Did the proton move into a region of higher potential or lower …

The potential difference between points a and b is

Asked by admin @ in Physics viewed by 293 persons

61. The potential difference between points A and B is (a) 10 V(c) 14 V(b) 12 V(d)0V​

The plot of the variation of potential difference across

Asked by admin @ in Physics viewed by 258 persons

The plot of the variation of potential difference across a combination of three identical cells in series, versus current is as shown here. What is the emf of each cell?

Why do we need different rooms in a house

Asked by admin @ in English viewed by 322 persons

Why do we need different rooms in a house​

If the potential difference across a resistor is doubled

Asked by admin @ in Physics viewed by 318 persons

"If the potential difference across a resistor is doubled: "? "A. only the current is doubled B. only the current is halved C. only the resistance is doubled D. only …

Potential difference va vb in the network shown is

Asked by admin @ in Physics viewed by 342 persons

A current of 2A flows in a system of conductors as shown . The potential difference (VA– VB) will be A) +2 V B) +1 V C) –1 V D) …

Most viewed questions in Physics


Jeevandeep health and physical education std 10 answers pdf

Asked by admin @ in Physics viewed by 11078 persons


Hc verma physics class 9 solutions of describing motion

Asked by admin @ in Physics viewed by 2674 persons


How to leave nightmare land answer key

Asked by maham237 @ in Physics viewed by 1600 persons



Base area and stability of some objects with different shapes

Asked by admin @ in Physics viewed by 1535 persons


Which of the following statements about safe lifting are correct

Asked by admin @ in Physics viewed by 1519 persons


Porous water-absorbing mass of fibers

Asked by wiki @ in Physics viewed by 1500 persons



Absorption of water by filter paper is due to

Asked by admin @ in Physics viewed by 1441 persons


A composite wire of uniform diameter 3mm

Asked by admin @ in Physics viewed by 1408 persons


At a distance l 400m from the traffic light

Asked by admin @ in Physics viewed by 1344 persons



A rocket of mass m is launched straight up with thrust f⃗ thrust.

Asked by maham237 @ in Physics viewed by 1322 persons


Mind map for light reflection and refraction class 10

Asked by admin @ in Physics viewed by 1151 persons



A thief runs at a speed of 10m s

Asked by admin @ in Physics viewed by 1099 persons


A 5.8 x 10 4 watt elevator motor can lift

Asked by maham237 @ in Physics viewed by 1085 persons