Calculate the velocity a spherical raindrop would achieve falling (take downward as positive) from 4.2 km in the following situations.

(a) calculate the velocity in the absence of air drag.

(b) calculate the velocity with air drag. take the size across of the drop to be 4.8 mm, the density of air to be 1.17 kg/m3, the density of water to be 1000 kg/m3, the surface area to be πr2, and the drag coefficient to be 1.0.

How much energy must a refrigerator absorb from 225 g of water so that the temperature of the water will drop from 35°c to 5°c

On a horizontal frictionless surface, a small block with mass 0.200 kg has a collision with a block of mass 0.400 kg. immediately after the collision, the 0.200 kg block is moving at 12.0 m/s in the direction 30° north of east and the 0.400 kg block is moving at 11.2 m/s in the direction 53.1° south of east. use coordinates where the +x-axis is east and the +y-axis is north.(a) what is the total kinetic energy of the two blocks after the collision (in ) what is the x-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your ) what is the y-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your answer.)

Which of the following forces require physical contact? tension air resistance friction magnetic force applied force