## Why is it dangerous to stand in the upper deck of a double decker bus?

Why is it dangerous to stand in the upper deck of a double decker bus?

“a body is said to be more stable when its CENTER OF GRAVITY is kept as low as possible. In a double decker bus , the c.g. of our body is obviously at higher place than the lower deck.In addition , if we stand the c.g. goes the higher , which will lead for a great imballance to be followed by a severe fall off. Moreover,when the bus moves or jerks,in lower deck,the moment of deflecting force is tolerable . But in the upper deck,it’s tremendously high”

## Resistance and Resistivity

“Two wires A and B of equal lengths,different cross-sectional areas and made of same metal a)name the property which is same for both the wires. b)name the property which is different for both the wires”

Since both the wires are of same metal, the resistivity will be same for both whereas since the dimensions (Area of cross section here) are different, the resistance will be different

## Amateur Research

Ask Physics is looking for students from Kendriya Vidyalayas of Kerala who are interested in doing Research in any branch of Science.

You will be contacted by the concerned official.

## Optics

“when we exchange the lenses of compound microscope, then why it does not act as a telescope?”

## Sequence of Learning Physics

In what sequence should these chapters be prepared for my exams:-
units and dimensions,kinematics,laws of motion,work power and energy,motion of system of particles and rigid body dynamics,gravitation.

It is better to follow the same pattern as given in NCERT text book

## Problem from Kinematics

The speed of a train changes from36km/h to 72km/h in 10sec. calculate the distance travelled during this time

u=36km/h = 10 m/s

v=72 km/h=20 m/s

t=10 s

S=?

use v = u+ at to find a

a = 1 m/s2

Use v2-u2=2aS to find S

S = (400-100)/2 = 150 m

## The “Pulling Power” of flame

I would like to ask : does flame has its own pulling power ? e.g. when we blow out a candle , the wick often seems to be goin      with the blow . is it coz of our blow or is it the flame carrying it along with itself ? (Bikramjit Singh asks)

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