A man who weighs 75kg on the surface of the earth whose mass is 6*10^24kg. If the radius of earth is 6480km ,calculate the force of attraction between them.

Which statement best describes how private industry decides where to spend the money on research and development

What is the speed of an object at a given moment?

1. jay fills a wagon with sand (about 20 kg) and pulls it with a rope 30 m along the beach. he holds the rope 25° above the horizontal. the rope exerts a 20-n tension force on the wagon. how much work does the rope do on the wagon?