A sample started with 100 atoms of Element X. Sample X has a Half-Life of 5 years. If there are only 6 atoms of Element X left in the sample, how old is the sample, and how many Half-Lives have occurred? To answer the question, select the age of the sample AND the number of Half-Lives that have occurred.

Aball is thrown from the top of a building with an initial velocity of 21.9 m/s straight upward, at an initial height of 51.6 m above the ground. the ball just misses the edge of the roof on its way down, as shown in the figure. (a) determine the time needed for the ball to reach its maximum height. (b) determine the maximum height. (c) determine the time needed for the ball to return to the height from which it was thrown, and the velocity of the ball at that instant. (d) determine the time needed for the ball to reach the ground. (e) determine the velocity and position of the ball at t = 5.35 s.

1700 j of energy is lost from 0.14 kg object , the temperature decreases from 50°c to 45°c what is the specific heat of this object, amd what is the material ?

Why do atoms emit energy of only specific wavelengths