Mass, weight and density

Question 1

define gravitational field

Answer 1

region in which mass experiences a force due to gravitational field

Question 2

define gravitational filed strength (formula)

Answer 2

gravitational force per unit mass

Question 3

instruments to measure weight

Answer 3

spring balance and compression balance

Question 4

instruments to weigh mass (BE)

Answer 4

beam balance and electronic balance

Question 5

define mass

Answer 5

mass is the amount of matter in the body

Question 6

define weight

Answer 6

amount of gravitational pull acting on a body

Question 7

differences between mass and weight

Answer 7

• mass: scalar quantity
• weight: vector quantity
• mass: measured in kilograms (kg)
• Weight: measured in newtons (N)
• mass: constant regardless of gravitational field strength
• Weight: varies according to gravitational filed strength

Question 8

formula for conversion

Answer 8

W = m x g
weight (N) equals to mass (Kg) times gravitational field strength (N/Kg)

Question 9

formula for density

Answer 9

p = m / v
density equals to mass divided by volume

Question 10

formula for combined density

Answer 10

Cp = Cm / Cv
combined density equals to combined mass divided by combined volume

Question 11

what is the density of ice

Answer 11

0.92 g/cm3

Question 12

what is the density of water

Answer 12

1.0 g/cm3

Question 13

why does ice have a lower density than ice

Answer 13

for a given mass of ice and water, the volume of ice is greater than the volume of water. therefore although solid ice is not very dense as the molecules are not packed closely together. liquid water is more dense because molecules are closer together

Question 14

for the same mass does ice have more density or water

Answer 14

for the same mass ice has a greater volume than water therefore ice s less dense

Question 15

define inertia

Answer 15

reluctance of the body to change its state of rest or motion, due to its mass

Question 16

define density

Answer 16

mass per unit volume

Question 17

what happens to a density of a melting substance if its volume increases as it melts

Answer 17

density of the substance decreases as it melts. Since mass is constant, when volume increases the density decreases

Question 18

why is it dangerous to keep a sealed bottle of water that is fully filled in the freezer

Answer 18

when water is frozen its density decreases and volume increases causing expansion that causes the bottle to break

Question 19

does the density change if both the volume and the mass is divides by 2

Answer 19

no