Why do scientists assume that the early universe was much hotter and denser than the universe of today?

Why is it unwise to stir a pot of soup with a metal spoon?

A 900-N lawn roller is to be pulled over a 5.0-cm high curb

2 cycleists, 90 miles apart starting riding toward each other at some times one cycles twice as fast as the other if they meet 2 hrs later at what average speed is each cyclist traveling

List two ways of recording or measuring absolute time

What do all electromagnetic waves have in common? They can travel at the speed of light. They have the same wavelengths. They travel only through matter. They have nonmoving magnetic fields.

Meteoroids usually come from?

An astronomer sees two stars in the sky. Both stars are equally far from Earth, but the first star is brighter than the second star. Which of the following is a valid conclusion about the first star? It is larger than the second star.

Crane lifts a 1,052 kg car. What force in Newtons must the crane apply to the car to lift it?

Consider a circuit with a main wire that branches into two other wires. If the current is 10 A in the main wire and 4 A in one of the branches, how much current is in the other branch?

A negative charge of - 2 C and a positive charge of 4 C are separated by 84,681 m. What is the force between the two charges?