Aspacecraft of mass 1.00×103kg orbits the sun (mass 1.99×1030kg) in a circular orbit of radius 1.50×1011m (equal to the average distance from the sun to the earth). you wish to move the spacecraft into a smaller circular orbit around the sun of radius 1.08×1011m (equal to the average distance from the sun to venus). in doing this, what will be the change in the spacecraft's kinetic energy? neglect the gravitational pulls of the planets on the spacecraft.

The us government wants to allocate billions of dollars in the next 10 years to assure our future energy security. the funds will be spread among a variety of possible energy resources. where do you think the government should put the greatest support: solar energy, wind energy, clean coal, oil exploration, gas exploration, or a combination of sources? are there other efforts that should be explored? support your position with cited information for both questions.

You are driving directly behind a pickup truck, going at the same speed as the truck. a crate falls from the bed of the truck to the road. (a) will your car hit the crate before the crate hits the road if you neither brake nor swerve? (b) during the fall, is the horizontal speed of the crate more than, less than, or the same as that of the truck?

A10 kg box initially at rest is pulled 18 meters across a horizontal, frictionless surface by a 40 n force. what is the block’s final velocity over the 18 meters?