Download App

Gravitation — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceGravitation3 Marks
Question
Suppose a planet exists whose mass and radius both are half that of the earth. The acceleration due to gravity on the surface of this planet will be double? Justify.
✓

Answer

g on earth $=\frac{\text{GMe}}{\text{R}^2}$

$\text{Me}=\frac{\text{Me}}{2}$

$\text{R}=\frac{\text{R}}{2}-\text{R}^2$

$=\Big(\frac{\text{R}}{2}\Big)^2=\frac{\text{R}^2}{4}$

Now,

g of this planet $=\text{G}\frac{\Big(\frac{\text{Me}}{2}\Big)}{\frac{\text{R}^2}{4}}$

$=\frac{(4\text{GMe})}{2\text{R}^2}$

$=\frac{2\text{GMe}}{\text{R}^2}$

$=2(\text{g})$

Thus, the acceleration due to gravity becomes twice.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "Que-Ans (Each of 3 Mark )" from Gravitation→Gravitation — all question types→Science STD 9 question papers→Gujarat Board STD 9 question papers→Gujarat Board question paper generator→

Similar questions

What is upthrust? What are the quantities that can vary upthrust? How does it account for the floating of a body? When a partially immersed body is pressed down a little, what will happen to the upthrust?
→

What is the procedure of providing distinct and proper names to organisms?

→

Write down four main characters of angiosperms.

→

Give the fsour characteristics of algae.

→
Comment upon the following:
Rigidity, compressibility, fluidity, filling a gas container, shape, kinetic energy and density.
→
Explain how the human ear works.
→

Write short notes on:

Polio.

→
What forms the basis of classification of tissues present in plants and animals?
→

State and explain in brief the four major factors, which are causes of disease.

→
What is the advantage of using insect resistant varieties?
→