Ch 4 Mass, Weight and Density

Question 1

What is the SI unit for mass?

Answer 1

kg, kilogram

Question 2

What is the formula to find density?

Answer 2

density=mass/volume

p = m / V

Question 3

What is the SI unit for weight?

Answer 3

N, newton

Question 4

What is the formula for weight?

Answer 4

W=mg

W: weight (N)

m: mass (kg)
g: gravitational field strength (10 N/kg on Earth)

Question 5

What is the value for gravitational field strength on earth?

Answer 5

10 N/kg

Question 6

Define mass.

Answer 6

The amount of substance in a body.

Question 7

Define weight.

Answer 7

The force of gravity acting on an object.

Question 8

What is the SI unit for density?

Answer 8

kg/m³

Question 9

What is inertia?

Answer 9

The reluctance of an object to change either its state of rest or if it is moving, its motion in a straight line.

Question 10

What is the relationship between mass and inertia?

Answer 10

The greater the mass, the greater the inertia.

or

The smaller the mass, the smaller the inertia.

Question 11

What is the difference between mass and weight?

(There are 5 differences)

Answer 11

1) Mass is the amount of substance in the body. Weight is the force of gravity acting on the body
2) Mass is constant at any location. Weight depends on the acceleration due to gravity at the location.
3) Mass is a scalar quantity. Weight is a vector quantity.
4) Mass is measured in kilograms. Weight is measured in newtons.
5) Mass is measured using a beam balance. Weight is measured using a spring balance.

Question 12

Will the density of a substance change?

Explain your answer.

Answer 12

No. Density will not change.

Since density = mass / volume and mass and volume of substance does not chnage over time, density will not change.