An Alpha Particle (A Helium Nucleus,having Charge +2e and Mass

question 62

Multiple Choice

An alpha particle (a helium nucleus,having charge +2e and mass 6.64 × 10^-27 kg) moves head-on at a fixed gold nucleus (having charge +79e) .If the distance of closest approach is 2.0 × 10^-10 m,what was the speed of the alpha particle when it was very far away from the gold? (k = 1/4πε₀
,

• A)2.3 × 10⁵ m/s
• B)4.6 × 10⁵ m/s
• C)2.3 × 10⁶ m/s
• D)4.6 × 10⁶ m/s

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Definitions:

Present Value

The present worth of a sum of money or cash flows expected in the future, based on a certain rate of return.

Cash Flow

The combined value of financial transactions into and out of an enterprise, crucially affecting its cash reserves.

Present Value

is the current worth of a future sum of money or stream of cash flows given a specified rate of return.

Discount Rate

The rate of interest utilized to calculate the current value of future cash flows in a discounted cash flow assessment.