A disc is free to rotate in a horizontal plane about an axis through its centre o. A small object p is placed on the disc so that op=0.2m. Contact between the particle and the disc is rough and the coefficient of friction is 0.5. the disc then begins to rotate Find the angular velocity of the disc when the particle is about to slip

Which of the following explains why it took so long for the public to accept the negative health effects of smoking? a)people were waiting for counter reasons, and those were presented. b)scientists had not completely finalized their results, which took 30 years. c)cigarettes were cheaply available and media channels were very inefficient. d)cigarette manufacturers were trying hard to bring an alternative into the market

This is the substance(s) formed in a chemical reaction.

Match each vocabulary term to its definition. 1. electrons neutral subatomic particles found in the nucleus of the atom 2. neutron lowest energy position of an electron in an atom 3. photon the path of an electron around the nucleus of an atom 4. ground state negatively charged, subatomic particles 5. protons packet of energy of specific size 6. element substance with only one type of atom 7. orbital positively charged, subatomic particles found in the nucleus of the atom