Si la velocidad de un bloque unido a un resorte está dada por la ecuación V= 7 cos(8t+0,5π)m/s, determine el módulo de la aceleración máxima si w = 8 rad/s

Does anyone know how to solve this problem? i really need . i made an attempt but i just cant get it. a metal rod is 25.000 cm long at 25.0 degrees celsius. when heated to 102.0 degrees celsius, it is 25.054 cm long. what is the coefficient of linear expansion for this metal.

What is the orbital period of a spacecraft in a low orbit near the surface of mars? the radius of mars is 3.4×106m.

The illuminance of a surface varies inversely with the square of its distance from the light source. if the illuminance of a surface is 120 lumens per square meter when its distance from a certain light source is 6 meters, by how many meters should the distance of the surface from the source be increased to reduce its illuminance to 30 lumens per square meter?