Physics 101
Homework #6

1) The plum-pudding model of the atom was proposed by,

a) Democritus b) J.J. Thomson c) E. Rutherford d) N. Bohr

2) The atomic number of an element represents its number of_______in the nucleus

a) electrons b) protons c) neutronsd) gravitons

3) The radioactive isotope, ¹⁹N, has how many neutrons in its nucleus?

a) 7 b) 18 c) 12 d) 11

4) When a marshmallow collapses to half its original volume by squeezing it, its density is

a) Doubled b) Halved c) Unchanged

5) Compared to the density of a liter of water, the density of a liter of ice is

a) less b) more c) same

6) A  block has a density of 2 g/cm³ and a volume of 2 m³. What is the block’s mass?

a) 4000 g b) 40,000 g c) 400,000 g d) 4,000,000 g

7) Doubling the linear size of an object increases its area by

a) 4 and its volume by 6 b) 2 and its volume by 4

c) 2 and its volume by 8 d) 4 and its volume by 8

8) A spring is stretched 20 cm by a suspended 1 kg block. If 2 such springs side by side are

used to suspend the block, so each spring supports 1/2 the weight of the block, then each spring

will stretch

a) 5 cm b) 10 cm c) 20 cm d) 30 cm

9) Convert 1000 kg/m³to g/cm³

a) 1 g/cm³ b) 10 g/cm³ c) 100 g/cm³ d) 1000 g/cm³

10) The pressure in a liquid depends on liquid

a) density b) depth c) both of these d) neither of these