A ball is whirled at the end of a string in a horizontal circle at 0.60m in radius at the rate of 0.5Hz. Find the ball's speed and centripetal acceleration. Please help!!

How does the formation of intrusive and extrusive igneous rocks differ?

If 150 kcal of heat raises the temperature of 2.0 kg of a material by 400 f°, what is the specific heat capacity of the material? 0.75 kcal/kg ∙ c° 1.35 kcal/kg ∙ c° 0.19 kcal/kg ∙ c° 0.34 kcal/kg ∙ c°

Which pair below describes isotopes of the same element? a) an atom with 6 protons and 8 neutrons - an atom with 8 protons and 6 neutrons b) an atom with 6 protons and 6 neutrons - an atom with 6 protons and 7 neutrons c) an atom with 8 protons and 8 neutrons - an atom with 7 protons and 8 neutrons d) an atom with 7 protons and 6 neutrons - an atom with 6 protons and 6 neutrons