Home » Ask & Discuss » Physics. » Mechanics « Back to Discussion

Mechanics

Hot goIITian

Joined:	9 Sep 2007
Post:	130

21 Sep 2007 21:22:00 IST

0 People liked this

468

hcv ques

None

A body starts bslipping down an incline and moves half meter in half seconds how long will it take to move the next half meter.

Share this article on:

Comments (3)

Bipin Dubey

Forum Expert

Joined: 23 Jan 2007

Posts: 7942

21 Sep 2007 21:55:09 IST

Like 1 people liked this

Use s = ut + (1/2)at² = (1/2)at²

At t₁=1/2, s=1/2 :

1/2 = u(1/2) + (1/2)a(1/2)²

a = 4 (for u=0)

When s=1 :

1 = ut₂ + (1/2)at₂²

t₂² = 2/a = 2/4 = 1/2

t₂ = 1/

2

Hence time taken to move next 1/2 metre = t₂ - t₁ = 1/

2 - 1/2 sec

Love Shah

New kid on the Block

Joined: 8 Jun 2007

Posts: 21

21 Sep 2007 23:02:30 IST

Like 0 people liked this

let the mass of the body be m, and angle of inclination be theta.

ignoring friction,

mg.sin(theta) = m.a

a=g sin(the.)

1/2= 0 + 1/2 .gsin(theta) .(1/2)^2

= sin(theta) = 4/10

= a= 4

v ( after have second) = (2*4*1/2) ^ 1/2

v= 2

now

1/2 = 2t + 2t^2

t= 0.21 seconds

Ignore the negative value in quad. since time cant be -ve.

Plz. rate me!!!

Rohan Bhattacharjee

Hot goIITian

Joined: 5 Jun 2007

Posts: 101

21 Sep 2007 23:18:28 IST

Like 0 people liked this

gr8 work

Quick Reply

Reply

	Some HTML allowed.
	Keep your comments above the belt or risk having them deleted.
	Signup for a avatar to have your pictures show up by your comment
	If Members see a thread that violates the Posting Rules, bring it to the attention of the Moderator Team