Ce lucru mecanic trebuie efectuat pt a mari viteza unui corp de la vi 12 m/s la v2=20 m/s pe o distanta orizontala de d=60 m, daca forta de frecare este Fr=24 N?Masa corpului este de 10 kg

What is hidden during a lunar eclipse? isn't the moon hidden?

Two students, each riding bicycles, start from the same apartment building and ride to the same building on campus, but each takes a different route. the first student rides 1100 m due east and then turns due north and travels another 1430 m before arriving at the destination. the second student heads due north for 1930 m and then turns and heads directly toward the destination.at the turning point, how far is the second student from the destination?

Large electric fields in cell membranes cause ions to move through the cell wall. the field strength in a typical membrane is 1.0 x 10 7 n/c. what is the magnitude of the force on a calcium ion with charge +e? what is its acceleration? is it possible for a particle with the same charge as as calcium to have a different acceleration if placed at this location? what would change the acceleration: mass of the particle? diameter of the particle?