Motion in One Dimension Exe-2C Very Short Answer Physics Class-9 ICSE Selina Publishers

Motion in One Dimension Exe-2C Equations of Motion Very Short Answer Type for Class-9 ICSE Concise Physics. There is the solutions of Very short Answer and Long answer type Questions of your latest textbook which is applicable in 2023-24 academic sessionVisit official Website CISCE for detail information about ICSE Board Class-9.

Motion in One Dimension Exe-2 C Equations of Motion Very Short Answer

(ICSE Class – 9 Physics Concise Selina Publishers)

 Board ICSE Class 9 Subject Physics Writer / Publication Concise selina Publishers Chapter-2 Motion in One Dimension Exe – 2 C Equations of Motion Topics Solution of Exe-2(C) Very Short and Long Answer Type Academic Session 2023-2024

Exe-2C Equations of Motion Very Short Answer Type

Ch-2 Motion in One Dimension Physics Class-9 ICSE Concise

Page 60

Question 1. Write three equations of uniformly accelerated motion relating the initial velocity (u), final velocity (v), time (t), acceleration (a) and displacement (S).

Three equations of a uniformly accelerated motion are

v = u + at

s = ut + (1/2)at2

v2 = u2 + 2as

Question 2. Write an expression for the distance S covered in time t by a body which is initially at rest and starts moving with a constant acceleration a.

Distance = s, time = t, initial velocity u = 0 and acceleration = a.

Using the second equation of motion and substituting the above values we get,

s = ut + (1/2) at2

Exe-2C Equations of Motion Long Answer Type

Motion in One Dimension Exe-2C Very Short Class-9 ICSE

Page 60

Question 1. Derive the following equations for uniformly accelerated motion:

(i) v = u + at

(ii) s = ut + (1/2) at2

(iii) v2 = u2 + 2aS

where the symbols have their usual meanings.

Derivation of equations of motion

First equation of motion:

Consider a particle moving along a straight line with uniform acceleration ‘a’. At t = 0, let the particle be at A and u be its initial velocity, and at t = t, let v be its final velocity.

Acceleration = Change in velocity/Time a = (– u)/t at = v – uv = u+ at … First equation of motion.

Second equation of motion:

Average velocity = Total distance traveled/Total time takenAverage velocity = s/t …(1)

Average velocity can be written as (u+v)/2 Average velocity = (u+v)/2 …(2)

From equations (1) and (2) s/t = (u+v)/2 …(3)

The first equation of motion is v = u + at.

Substituting the value of v in equation (3), we get

s/t = (at)/2 s = (2att/2 = 2ut at2/2 = 2ut/2 + at2/2

s = ut + (1/2) at2 …Second equation of motion.

Third equation of motion:

The first equation of motion is v = u + at. v – u = at … (1)

Average velocity = s/t …(2)

Average velocity =(u+v)/2 …(3)

From equation (2) and equation (3) we get,

(u v)/2 = s/t …(4)

Multiplying eq (1) and eq (4) we get,

(v – u)(v + u) = at × (2s/t) (v – u)(v + u) = 2as

[We make the use of the identity a2 – b2 = (a + b) (a – b)]

v2 – u2 = 2as …Third equation of motion.

—  : End of Motion in One Dimension Exe-2C Equations of Motion Very Short and Long Answer Type  Solutions :–

Thanks