Mass and Weight | Gravitation | Assessment | English | Grade 9

Calculate the mass of a person on earth whose weight is 800 N.

• 80 g

• 80000 g

• 800 g

• 8 g

Answer explanation

W = mg 800 = m × 10 m = 80 kg = 80000 g

Tags

NGSS.MS-PS2-4

Ratio of mass of earth and moon is 10:1. How will the gravitational force of moon on earth vary with the gravitational force of earth on moon?

• Gravitational force of earth on moon > Gravitational force of moon on earth

• Gravitational force of earth on moon ≥ Gravitational force of moon on earth

• Gravitational force of earth on moon = Gravitational force of moon on earth

• Gravitational force of earth on moon < Gravitational force of moon on earth

Answer explanation

We know according to universal law of gravitation all the objects attract each other with same force. Hence, Gravitational force of earth on moon is equal to Gravitational force of moon on earth So, option 3 is correct

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-4

Two sisters A and B having of weight 40 N and 35 N can pick up boxes with mass 12 kg and 15 kg respectively on earth. How much weight do you think they carry together on moon?

• 27kg

• 4.5 kg

• 162kg

• None of these

Answer explanation

A person can carry 6 times heavier mass on moon as acceleration due to gravity on moon is 1/6 times to that on earth. So, weight they can carry together on moon = 6 × 27 = 162 kg

Tags

NGSS.MS-PS2-4

A person travelled from equator to poles, its ___.

• Weight will decrease

• mass will decrease

• Weight will increase

• Its weight and mass remains same

Answer explanation

A person travelled from equator to poles, its weight will increase as gravity is more in poles.

Mass of an astronaut on moon is M. What will be its weight on moon and on earth, if acceleration due to gravity on earth is 9.8 m/s²?

• 1.6 M and 9.8 M

• 6M and 9.8 M

• 18M and 3 M

• 3M and 18 M

Answer explanation

Mass of Astronaut on moon= M g on moon = g on earth/6 = 9.8/6 =1.6 m/s² Weight on moon = 1.6 M Weight on earth = 9.8 M

Tags

NGSS.MS-PS2-4

Which of the following is true about mass and weight?

• A heavy object has more weight.

• Weight and mass are interchangeable.

• Weight is force and mass is a measure of inertia.

• Both 1 and 3

Answer explanation

Weight and mass are not same, so they are not interchangeable. So, Option 2 in incorrect A heavy object has more mass, not weight. So, Option 1 is eliminated. Therefore, option 4 is also eliminated. Weight is force and mass is a measure of inertia. So, option 3 is correct