Ryan ran two combs through his hair. He hung one comb from a stan… - Vidyadip

Question

Ryan ran two combs through his hair.
He hung one comb from a stand using a thread.
Ryan brought the other comb close to the irst comb.
The picture below shows the result.

$1.$ Why did the comb move away from the other$?$
$2.$ Ryan repeats the activity using a pair of glass rods in place of the combs.
What would be the result$?$
$A.$ The hanging rod will move away
$B.$ The hanging rod will come closer
$C. $ The hanging rod will show no change
$D. $ The hanging rod will start spinning

✓

Answer

$1.$ Mentions that the combs are likely charged.
$2. A.$ The hanging rod will move away

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 "case /data -based (4 Marks)" from Some Natural Phenomena→Some Natural Phenomena — all question types→Science STD 8 question papers→Gujarat Board STD 8 question papers→Gujarat Board question paper generator→

Similar questions

The picture shows four types of shoe soles.

$9.$ Which shoe sole provides the best grip and friction while walking$?$
$A.$ Sole$1$
$B.$ Sole $2$
$C.$ Sole $3$
$D.$ Sole $4$
$10.$ Why do weightlifters apply chalk powder on their palms while lifting weights$?$

The table shows the caloriic value and pollutants released by four types of fuels.

Fuel	Caloriic value (kilojoule / kg)	Pollution factor
Type $1$	$25000 - 33000$	$CO_2,$ sulphur oxides and Nitrogen oxides
Type $2$	$55000$	$CO_2,$ Water vapour
Type $3$	$45000$	Carbon monoxide, $CO_2,$ Nitrogen oxides
Type $4$	$35000 - 40000$	$CO_2$ and Methane

$8.$ Which fuel can boil the water in a vessel the fastest$?$
$A.$ Type $1$
$B.$ Type $2$
$C.$ Type $3$
$D.$ Type $4$
$9.$ Which fuel can cause acid rain on combustion$?$
$A.$ Type $1$ only
$B.$ Type $4$ only
$C.$ Both Type $1$ and Type $3$
$D.$ Both Type $2$ and Type $4$
$10.$ Which fuel type is likely to be biogas$?$
$A.$ Type $1$
$B.$ Type $2$
$C.$ Type $3$
$D.$ Type $4$

Two groups of students are playing tug-of-war.

$2.$ Choose the correct direction of force applied by Group $1$ and Group $2.$

$3.$ Group $1$ is pulling with $250\ N$ force and Group $2$ is pulling with $300\ N$ force.
What would be the likely position of the two groups after a minute of pulling$?$

The picture shows the life cycle of a moth.

$9.$ What can be concluded from the picture$?$
Circle ‘Yes’ or ‘No’ for the correct response.

Can this be concluded from the picture?	Yes or No
Moth is an oviparous animal.	Yes/No
A moth looks different in each stage of its life cycle.	Yes/No
There are two different stages in the life cycle of a moth.	Yes/No

The material X is a fossil fuel. It is formed from the buried large land plants (vegetation) by a very slow process Y. When X is heated in the absence of air, it gives three products A, B and C.
A is used in steel making B is used as an industrial fuel, whereas the product C has been traditionally used for metalling the roads. It is now replaced by a petroleum product, bitumen.
Now give the answer of the following questions.
(i) What is the material X ?
(ii) What is the physical state and colour of X ?
(iii) Name the processes Y.
(iv) What are the products A, B and C ?

Erik dumped four types of domestic waste in separate land pits.
He covered the pits and left them undisturbed for a year.
The table below shows what he observed after a year.

Waste $1$	Waste $2$	Waste $3$	Waste $4$
Fully decomposed	Not decomposed at all	Fully decomposed	Not decomposed at all

$9.$ Which type of waste(s) is most likely to cause soil pollution$?$

The picture shows the basic parts of a salmon ish sperm.

$7.$ Which part of the sperm helps it to swim in water and reach the egg$?$
$8.$ Which of these animals reproduce by external fertilization?
$A.$ Snake
$B.$ Frog
$C.$ Horse
$D.$ Elephant

The table shows the properties of four water samples.

Water Sample	Smell	Colour
Sample $1$	No smell	Slightly muddy
Sample $2$	Strong bad smell	Muddy and greenish
Sample $3$	Very light smell	Colourless
Sample $4$	No smell	Colourless

$6$. Which water sample is likely to be least polluted$?$
$A.$ Sample $1$
$B.$ Sample $2$
$C$. Sample $ 3$
$D$. Sample $4$
$7.$ In which water source will the survival of aquatic animals be the most dificult$?$
$A.$ Source of Sample $1$
$B.$ Source of Sample $2$
$C.$ Source of Sample $3$
$D.$ Source of Sample $4$

The picture shows four different rubber tubes.

$5.$ Which tube will experience the least friction while rolling on a surface?
Explain your answer.
$6.$ Which of these would affect the amount of friction generated on a moving object$?$
Circle ‘Yes’ or ‘No’ for the correct response.

Does this Affect the Amount of Friction Generated?	Yes or No
Mass of the object	Yes/No
Surface area of the object	Yes/No
Roughness of the object	Yes/No

Which of these is true about the four sound waves$?$
Circle ‘Yes’ or ‘No’ to mark your responses.

Animal	Frequency range of sound waves
Elephant	$15–12000\ Hz$
Human	$20–22000\ Hz$
Dog	$65–45000\ Hz$
Chicken	$125–2000\ Hz$

$5.$ A cat made a purring sound that had a frequency of $35\ Hz.$
Which of the animals mentioned in the table can hear the purring$?$
$A.$ Only human
$B.$ Only elephant
$C.$ Dog and chicken
$D.$ Elephant and human
$6.$ Which of the following sounds can be classiied as noise for humans$?$
$A.$ Sounds that are softer than $20\ dB$
$B.$ Sounds that are in between $20\ dB$ and $40\ dB$
$C.$ Sounds that are between $40\ dB$ and $80\ dB$
$D.$ Sounds that are louder than $80\ dB$
$7.$ Which of these will reduce noise pollution?
Circle ‘Yes’ or ‘No’ to mark your responses.

Will this reduce noise pollution?	Yes or No
Regulating the use of loudspeakers	Yes/No
Setting up more thermal power plants	Yes/No
Using more electric vehicles	Yes/No