What are the two key variables that are required for work to occur? Select all that apply 3 points
time
Force
Displacement
Option 4

What is the average speed of a car that travels 40 mph for 1 hour and 60 mph in another hour?

How is sound energy produced a. vibrating objects b. objects being heated c. temperature differences d. stationary objects

Aleaky 10-kg bucket is lifted from the ground to a height of 15 m at a constant speed with a rope that weighs 0.7 kg/m. initially the bucket contains 45 kg of water, but the water leaks at a constant rate and finishes draining just as the bucket reaches the 15-m level. find the work done. (use 9.8 m/s2 for g.) show how to approximate the required work by a riemann sum. (let x be the height in meters above the ground. enter xi* as xi.) lim n → ∞ n (9.8)(45−3 xi) i = 1 δx express the work as an integral. 0 dx evaluate the integral. (round your answer to the nearest integer.) j