A hot air balloon rising straight up from a level field is tracked by a range finder located a horizontal distance of 500m from the lift-off point. At the moment the range-finder's elevation angle is pi/4 , the angle is increasing at a rate of 0.14 rad/min. How fast is the balloon rising at the moment?

A2-kg bowling ball is 2.5 meters off the ground on a post when it falls. just before it reaches the ground, it is traveling 7 m/s. assuming that there is no air resistance, which statement is true?

1. how to locate the image in converging(concave) mirror and diverging (convex) mirror with salt. 2. how to locate the image in a converging (convex) lens and diverging (concave) lens with salt.

Consider two regions of space containing a static electric field, region a and region b. in region a the equipotential lines are more closely spaced than those in region b. what can be said about the relative strength of the electric field in the two regions? a) the electric field in region a is stronger th