At 9 a.m. on Monday a radioactive sample contained four million nuclei. At 9 a.m. on Friday three million of these nuclei had decayed. The half-life of this sample is:

a. 5 days b. 4 days c. 3 days d. 2 days e. 1 day


d

Physics & Space Science

You might also like to view...

How would the self-inductance, L, of a coil change if you would increase its radius by a factor of two and increase its length by a factor of two?

A) L would not change. B) L would be doubled. C) L would be quadrupled. D) L would be halved. E) L would be reduced by 4.

Physics & Space Science

What is the approximate surface temperature of an F star?

A) 12,000 K B) 6,000 K C) 7,000 K D) 5,000 K

Physics & Space Science

Which of the following elements will most likely form an ion with a +2 charge?

A) Na B) Mg C) Ne D) Si E) Cl

Physics & Space Science

You throw a ball straight up, it peaks out, and then comes back down to you. During this motion, the velocity and acceleration

a. always point in the same direction b. always point opposite to each other c. sometimes point in the same direction, and other times point opposite to each other d. depend on the way the ball is thrown e. depend on the mass of the ball

Physics & Space Science