Question

Hello

Q1. Verify v²-u²=2as by calculus method

Q2. What is parallax method? Give answer in about 40 words

Class 11

Physics


THANK YOU​

Answer 1

Solution:-

To prove :-

$\huge 2as = v^2 - u^2$

By calculus method.

Proof :-

Let a body moves with constant acceleration a by initial velocity u and after time t it's final velocity becomes v.

then,

→$\huge \vec{a} = \dfrac{dv}{dt}$

→$\huge a = \dfrac{dv}{ds} \times \dfrac{ds}{dt}$

→$\huge a = \dfrac{dv}{ds}\times dv$

→$\huge \int_{u}^{v}v.dv$ $\huge = \int_{0}^{s}ads$

→$\huge [v]_u^v = a [s]_0^s$

→$\huge [\dfrac{v^2}{2}]_u^v = a [s]_0^s$

→$\huge \dfrac{v^2 - u^2}{2}= as$

→$\huge v^2 - u^2 = 2as$ proved..

Parallax method :-

The method which is used to measure the large distances such as distance between sun and earth moon and earth etc is called parallax method.

When we see an object from both eyes the position of the object fluctuates when seen from one eye it is due to the parallax.

The direction along which an object is viewed subtended an angle between the two lines known as parallax angle.

For measuring the distance by parallax method we use the formula :-

★ $\huge \boxed{\sf{ r = \dfrac{l}{\theta}}}$

where $\theta$ is the parallax angle.

, r is the distance between the point of observation to the object, and l is the distance between the point of observations.

Answer 2

Question 1 :- verify v² - u² = 2as

Answer :-

Refer to the attachment number 1

Also, remember v (velocity) = dx/dt

$\rule{200}{2}$

Question 2 :- what is parralex method ?

Answer :-

It is the way to calculate the distance of the near by star or moon from the earth.

( In image 2 )

In parralex method we just calculate the angle of the star from the earth with the help of telescope, Far star doesn't change its post as it very far, So we observe the angle Φ1 and Φ2 with the telescope Φ2 is observed when Earth complete half revolution . We also know that 1AU = 1.49 × 10^15 m.

By solving it like Δ properties we can calculate distance of near by star

$\rule{200}{2}$