Question

True and False

15 The index of refraction is about 7.8 for glass.

16. Energy is always conserved.

17. A car traveling 40 miles in ½ hour is traveling at 20 mph.

18. 40 ^o C is hotter than 40^o F .

19. Objects with a density less than 1000 kg/m³ float.

20. Like charges repel and unlike charges attract

21. Electric current is more dangerous than voltage.

22.   Protons and electrons are found in the nucleus of atoms.

23 The atomic number of an element is the number of protons.

24. Electrons surround the nucleus of an atom and each has its own energy state.

25. An object that approaches you makes a sound having a higher pitch or frequency than normal.

26. The Doppler effect is a change in frequency due to the relative motion of a source of sound

	27. The amplitude of the wave is the time it takes it to pass a point.
28. When light passes through a lens it bends due to the property called refraction.

29. A magnifiing glass when used to enlarge letters on a page is producing a virtual image.

Answer 1

15 The index of refraction is about 7.8 for glass -- FALSE

16. Energy is always conserved.-- FALSE

17. A car traveling 40 miles in ½ hour is traveling at 20 mph. FALSE

18. 40 o C is hotter than 40o F . --- FALSE

19. Objects with a density less than 1000 kg/m^3 float. FLASE

20. Like charges repel and unlike charges attract--- TRUE

21. Electric current is more dangerous than voltage. -- TRUE

22. Protons and electrons are found in the nucleus of atoms.-- FLASE

23 The atomic number of an element is the number of protons.-- TRUE

24. Electrons surround the nucleus of an atom and each has its own energy state.- TRUE

25. An object that approaches you makes a sound having a higher pitch or frequency than normal.-- TRUE

26. The Doppler effect is a change in frequency due to the relative motion of a source of sound-- TRUE

27. The amplitude of the wave is the time it takes it to pass a point.-- FALSE

28. When light passes through a lens it bends due to the property called refraction.--TRUE

29. A magnifiing glass when used to enlarge letters on a page is producing a virtual image.--TRUE