Calculate the force to be applied to raise a 20kg block on an inclined plane with an angle of a 25°, at constant speed, if the coefficient of the kinetic friction is Uk= 0.25.

An object is 10. cm from the mirror, its height is 3.0 cm, and the focal length is 2.0 cm. what is the image height? (indicate the object orientation by including the + or - sign with the answer.) hi = cm +1.33 -1.33 +0.75 -0.75

Which notation is used to represent an alpha particle? a. b. c. d.

Would it be correct to say the doppler effect is the apparent change in the speed of a wave due to the motion of the source? be sure to fully explain your position using at least 3 complete content related sentences.