After the big bang started the universe 13.78 billion years ago, the universe began to rapidly expand. This rapid expansion caused the universe to cool down into a network of gaseous clouds composed mainly of which element?
O Oxygen
Hydrogen
O Neon
O Carbon

The percent efficiency of a machine can never be 100% (or greater), because in the real world some energy is always converted into a. heat b. work c. input force d. output force

(01.02 mc) nicole pushes her bike up a hill. overhead, the sun exerts a gravitational force on earth. which statement is true about the bike and earth? they both experience contact forces. they both experience non-contact forces. the bike experiences a non-contact force and earth experiences a contact force. the bike experiences a contact force and earth experiences a non-contact force. they both experience non-contact forces.

With physics question #5? for any !