One kilogram of the explosive TNT supplies an explosive energy of about 4.2×10^6 J. Let’s see what that energy can achieve in lifting objects from Earth’s surface to altitudes of hundreds of kilometers. We approach the issue through gravitational potential energy. Assume the acceleration due to gravity is constant at g = 9.81 m/s2 from Earth’s surface up to an altitude of 510 km above the surface. (A satellite at such an altitude would be in a “low Earth orbit.”) What is the gravitational potential energy, in joules, of a 1.0-kg object at that altitude, taking the reference level for gravitational potential energy (U = 0) at Earth’s surface.

Why don't you see your reflection in water with waves or repples

Determine the age of a fossil if it had only one eighth of its original carbon-14 content remaining?

Arunner is jogging at a steady 3.6 km/hr. when the runner is 2.9 km from the finish line, a bird begins flying from the runner to the finish line at 14.4 km/hr (4 times as fast as the runner). when the bird reaches the finish line, it turns around and flies back to the runner. even though the bird is a dodo, we will assume that it occupies only one point in space, i.e., a zero-length bird. how far does the bird travel? (b) after this first encounter, the bird then turns around and flies from the runner back to the finish line, turns around again and flies back to the runner. the bird repeats the back and forth trips until the runner reaches the finish line. how far does the bird travel from the beginning? (i.e. include the distance traveled to the first encounter)