Testing shows that a sample of wood from an artifact contains 12.5% of the original amount of carbon-14. Given that the half-life of carbon-14 is 5730 years, how old is the artifact? A. 22,920 years
B. 17,190 years
C. 11,460 years
D. 5730 years

Aturntable that spins at a constant 74.0 rpm takes 3.10 s to reach this angular speed after it is turned on. find its angular acceleration (in rad/s2), assuming it to be constant, and the number of degrees it turns through while speeding up.

Acentrifuge in a medical laboratory rotates at an angular speed of 3,700 rev/min. when switched off, it rotates through 54.0 revolutions before coming to rest. find the constant angular acceleration (in rad/s2) of the centrifuge. your response is within 10% of the correct value. this may be due to roundoff error, or you could have a mistake in your calculation. carry out all intermediate results to at least four-digit accuracy to minimize roundoff error. rad/s2

Ominge cade de la inaptimea de 3 metri apoi sare de la podea pina la inaltimea de 0,5 metri. determina a) forma traectoriei mingii. b) deplasarea mingii. c) drumul parcurs de minge. va rog foarte mult va dau coroana