You find a radioactive substance in the chemistry storage locker. You measure the mass of the substance and find that it is 5 grams. You do some research and find that this substance has a half-life of 10 seconds. How much mass of this substance was in the chemistry storage locker 1 hour before you found it? 0 10 grams O 40 grams O 120 grams O 320 grams O 640 grams O It is impossible to know the starting mass of any substance due to radioactive day.​

Why are some galaxies’ spectra blueshifted rather than redshifted? question 4 options:

The image shows the positions of a car on a roller coaster track. arrange the cars in order based on their gravitational potential energy. begin with the lowest potential energy and end with the highest.

Aball is thrown upward. at a height of 10 meters above the ground, the ball has a potential energy of 50 joules (with the potential energy equal to zero at ground level) and is moving upward with a kinetic energy of 50 joules. what is the maximum height h reached by the ball? consider air friction to be negligible. 1. h ≈ 10 m 2. h ≈ 50 m 3. h ≈ 30 m 4. h ≈ 40 m 5. h ≈ 20 m 003 10.0 points which of the two object shown below has the greatest kinetic energy? a m b 1 2 m v 2v 1. kinetic energies are the same. 2. a 3. b 4. unable to determine. 004 10.0 points tim, with mass 74.6 kg, climbs a gymnasium rope a distance of 3.1 m. the acceleration of gravity is 9.8 m/s 2 . how much potential energy does tim gain? answer in units of j. 005 10.0 points a car is moving at 64 miles per hour. the kinetic energy of that car is 5 × 105 j. how much energy does the same car have when it moves at 111 miles per hour? answer in units of j. 006 10.0 points an 102 kg man climbs up a 1 m high flight of stairs. the acceleration of gravity is 9.81 m/s 2 . w