As shown in the figure, the fixed smooth surface in the elevator has an inclination angle of 30 ° and the lower end of the spring on the inclined surface is connected with a wood block with a mass of M = 4kg. When the elevator descends at an acceleration of 2m / S ^ 2, the elevator will be able to move forward seek Spring force Write the support of the face to the block

As shown in the figure, the fixed smooth surface in the elevator has an inclination angle of 30 ° and the lower end of the spring on the inclined surface is connected with a wood block with a mass of M = 4kg. When the elevator descends at an acceleration of 2m / S ^ 2, the elevator will be able to move forward seek Spring force Write the support of the face to the block

Let the elastic force be f and the supporting force be n
From Newton's second theorem
F=(mg-ma)*sina=16N
N = (mg MA) * cosa = 16 * radical 3N